THE  UNIVERSITY 

OF  ILLINOIS 

LIBRARY 


<S_Q-p. 


UNIVERSITY  OF  ILLINOIS 

Agricultural  Experiment  Station 


BULLETIN  No.  207 


WASHING  OF  SOILS  AND  METHODS  OF 
PREVENTION 


BY  J.  G.  HOSIER  AND  A.  F.  GUSTAFSON 


URBANA,  ILLINOIS,  APRIL,  1918 


CONTENTS  OF  BULLETIN  No.  207 

PAGE 
AREA  OF  BROKEN  AND  HILLY  LAND  IN  ILLINOIS 513 

RAINFALL  IN  ILLINOIS 517 

RUN-OFF 518 

WORK  OF  MOVING  WATER 519 

KINDS  OF  EROSION  519 

EFFECTS  OF  EROSION  522 

Loss  of  Organic  Matter,  Nitrogen,  an'd  Phosphorus 522 

Changes  in  the  Physical  Character  of  the  Soil 525 

METHODS  OF  REDUCING  EROSION 526 

Reducing  Sheet  Washing 526 

Filling  and  Preventing  Gullies 536 

RECLAMATION  EXPERIMENTS  .  . .  543 


WASHING  OF  SOILS  AND  METHODS  OF 
PREVENTION 

BY  J.  G.  MOSIEE,  CHIEF  IN  SOIL  PHYSICS,  AND 
A.  F.  GUSTAFSON,  ASSISTANT  CHIEF  IN  SOIL  PHYSICS 

From  careful  measurements  made  of  twenty-seven  counties  in 
various  parts  of  Illinois,  it  has  been  determined  that  the  state  consists 
of  approximately  two-thirds  prairie  land  and  one-third  timber  land. 
A  considerable  proportion  of  the  latter  is  rolling  or  hilly,  but  there 
is  also  much  timber  bottom  land  and  some  level  timber  upland.  The 
total  area  of  the  state  is  56,650  square  miles,  or  more  than  36  million 
acres.  Of  this  large  area,  afegnt-foy  nnA  rmn  half  million  TMrran  irr 
rolling  or  hilly  and  subject  to  serious  erosion.  A  large  part  of  this 
land  can  be  cultivated  and  cropped,  but  every  practical  means  should 
be  employed  to  prevent  its  rapid  ruin  by  erosion. 

Some  Illinois  land  has  already  been  completely  ruined.  Aban- 
doned fields,  impoverished  by  erosion  beyond  all  possibility  of  reclam- 
ation by  ordinary  methods,  are  now  to  be  found,  especially  in  the 
broken  and  hilly  areas  of  the  southern  half  of  the  state.  In  most 
cases  this  land  should  never  have  been  deprived  of  its  protecting 
forest,  the  chief  thing  that  made  it  valuable  in  the  first  place. 


FIG.  1. — ADVANCED  STAGE  OF  EROSION  IN  KANDOLPH  COUNTY 

513 


S14 


BULLETIN  No.  207 


[April, 


TABLE  1. — APPROXIMATE  ABE  A  OP  BROKEN  AND  HILLY  LAND  IN  THE  COUNTIES 
OF  ILLINOIS  COVERED  BY  THE  SOIL  SURVEY  PREVIOUS  TO  1917 


County 

Total  area 
of  county 

Area  of 
broken  and 
hilly  land 

Percentage  of 
broken  and 
hilly  land 

Adams  .        

sq.  rm. 
833  00 

sq.  rm. 
233  00 

percent 
28  00 

Alexander  

290.00 

88.00 

30  00 

Bond  

371  88 

74  48 

20  01 

Boone  

288.00 

10.00 

3.47 

Brown  

300.00 

130.00 

43  30 

Bureau  

877  00 

79  80 

9  00 

Champaign  .  . 

988.15 

3.06 

.31 

Clay  

467.73 

69  25 

14  85 

Clinton  .           

498  00 

15  25 

2  50 

Cook  

963.00 

11.00 

1  14 

Crawford  

453.00 

25.02 

5.52 

Cumberland  

340.43 

34.98 

10  28 

DeKalb  

632.70 

.43 

07 

DeWitt..   .     . 

406  00 

19"00~ 

475^ 

Douglas  

420.00 

1.50 

36 

DuPage  

326  98 

7  57 

2  32 

Edgar  

617.27 

45.41 

7  36 

Edwards  

218.41 

55.71 

25.95 

Franklin  

436.00 

30.00 

6  88 

Grundy  

429.00 

3.00 

70 

Hamilton  

438.00 

83.00 

18.70 

Hancock  

765  00 

200.00 

26  14 

Har  din  

168.00 

132.90 

79.10 

Henderson  

374  00 

54.00 

14  43 

Iroquois  

1  123  00 

2  00 

18 

Jackson  

558.00 

252.00 

47.00 

Jersey  

360  00 

151  20 

42  00 

Jo  Daviess  

656.00 

421.00 

64.20 

Johnson  

336.00 

227.07 

67.60 

Kane  

513.14 

6.38 

1.24 

TKankakee  ,  ,    , 

670  13 

.92 

,14_t 

Knmr  ,...,...    ,  ,  ,    , 

720  69 

133  71 

ISrfiff 

Lake  

482.82 

38.50 

7.98 

LaSalle  

1  156.83 

41.12 

3.55 

Lawrence  

362  00 

44  25 

1.17 

Livingston  

1  030  00 

1  50 

.14 

McDonough  

573  94 

144  41 

25  16 

McHenry  

609.52 

4.92 

.81 

McLean  

1  168.60 

27.43 

2.35 

Macon  

606.00 

19  30 

3.36 

Marion  

570  00 

46  75 

8  20 

Mason  

653.99 

10.01 

1.81 

Massac  

238.00 

100.00 

42.00 

Monroe  

385  00 

130.00 

33.30 

Montgomery.  . 

702.00 

64.00 

9.10 

1918] 


WASHING  OF  SOILS  AND  METHODS  OP  PREVENTION 


515 


TABLE  1. — Concluded 


County 

Total  area 
of  county 

Area  of 
broken  and 
hilly  land 

Percentage  of 
broken  and 
hilly  land 

Moultrie  

sq.  mi. 
341  06 

sq.  im. 
2  19 

percent 
64 

Ogle  

768  00 

3)  00 

4  69 

Peoria  

620  60 

172  59 

27  81 

Perry  

430  00 

86  00 

20  00 

Pike  

798  89 

381  .  78 

47  79 

Richland  

360  00 

45  75 

12  80 

Rock  Island  

441  00 

109  00 

24  77 

Saline  

377.56 

101.11 

26.78 

Sangamon  

869  48 

59.08 

6  78 

Scott  

245-.  28 

51.50 

20.99 

Shelby  

780.00 

70.00 

9.00 

St.  Glair  

680.00 

"29.00 

19.00 

Tazewell  

646  91 

67.18 

10.39 

Vermilion  

928.00 

36.00 

4.05 

White  

512.00 

42.00 

8.30 

Whiteside  

700.09 

74.24 

10.59 

Winnebago  

515.66 

37.17 

7.21 

Total  

35  291.74 

5  365.04 

Average  for  area  surveyed . 


15.20 


Besides  the  broken  and  hilly  land,  there  is  a  large  area  of  undu- 
lating to  rolling  land,  both  timber  and-  prairie,  that  has  not  been 
badly  damaged  as  yet,  but  which  with  continued  cropping  and  con- 
sequent loss  of  organic  matter  is  becoming  more  and  more  subject  to 
injurious  surface  erosion.  The  area  of  undulating  timber  soil  is 
approximately  tjae^ame  as  that  of  the  hilly  land,  shown  in  Table  1. 

In  the  siiniyiwe  Bounties  of  Illinois  that  have  been  covered  by  the 
detailed  soil  survey,  -«r8  percent  of  the  land,  as  an  average,  is  of  such 
a  character  that  it  is  subject  to  serious  damage  from  surface  washing. 
Table  1  gives  the  area  of  these  counties,  together  with  the  area  and 
the  percentage  of  broken  and  hilly  land  in  each, 


516 


BULLETIN  No.  207 


[April, 


FIG.  2. — A  GULLY  IN  MCHENRY  COUNTY 
Even  gravelly  glacial  material  erodes  badly  under  certain  conditions. 


FIG.  3. — FKOSION  IN  OGLE  COUNTY 

Not  a  bad  slope,  but  even  with  the  comparatively  low  rainfall  of  northern  Illi- 
nois, considerable  damage  may  be  done  when  gullies  are  neglected. 


1918} 


WASHING  OF  SOILS  AND  METHODS  OF  I>REVENTION 


517 


FIG.  4. — ADVANCED  STAGE  OF  EROSION  IN  ADAMS  COUNTY,  DUE  TO  A  SUBSTRATUM 

OF  INCOHERENT  SAND 


RAINFALL  IN  ILLINOIS 

Illinois  lies  in  the  belt  of  prevailing  westerly  winds.  Much  of 
the  rainfall  comes  in  moderate  or  gentle  rains,  during  which  a  large 
proportion  of  the  water  enters  the  soil,  but  in  the  summer  particu- 
larly there  are  very  heavy  rains,  and  as  the  soil  is  unable  to  absorb  so 
much  water  in  such  a  short  time,  much  of  it  runs  off  the  sloping  land. 
From  Table  2,  which  shows  the  average  rainfall  by  seasons  in  the 
various  sections  of  the  state,  it  will  be  seen  that  the  greatest  rainfall 
is  in  the  spring  and  summer  months,  when  the  soil  is  in  the  best 
condition  to  absorb  water ;  but  in  spite  of  this  fact  there  is  an  enor- 
mous run-off  from  the  rolling  land  of  the  state. 

TABLE  2. — AVERAGE  SEASONAL  RAINFALL  IN  ILLINOIS 


District 

Winter 

Spring 

Summer 

Autumn 

Extreme  northern1  .  .  .  '. 
^Central-northern2  .... 

inches 
5.44 
5-.  80 
6.82 
8.80 
10.66 

percent 
16.0 
16.8 
18.0 
21.2 
24.8 

inches 
9.34 
9.61 
10.43 
11.75 
12.38 

percent 
27.4 
27.9 
27.9 
28.3 
28.5 

inches 
11.22 
10.75 
11.04 
11.75 
10.70 

percent 
33.0 
31.6 
30.7 
28.3 
24.7 

inches 
7.99 
8.11 
8.60 
9.18 
9.54 

percent 
23.6 
23.7 
23.4 
22.2 
22.0 

Central  

Central-southern^  . 

Extreme  southern1  

4866  to  1915.     =1850  to  1915. 


518 


BULLETIN  No.  207 


[April, 


RUN-OFF 

The  extent  to  which  washing  occurs  depends  upon  the  amount  of 
surface  run-off.  The  amount  of  run-off  and  the  effect  which  it  has 
depends  to  a  large  extent  upon  the  character  of  the  soil  and  subsoil, 
the  length  and  steepness  of  the  slope,  the  tillage  practiced,  and  the 
vegetation  growing  upon  it.  Because  of  these  many  varying  condi- 
tions, it  is  difficult  to  compute  the  amount  of  run-off.  Considerable 
work  has  been  done,  however,  which  may  form  the  basis  for  a  fair 
estimate.  Table  3  gives  the  results  of  the  work  of  Mr.  F.  H.  Newell, 
formerly  Chief  Hydrographer  of  the  U.  S.  Geological  Survey. 

TABLE  3. — PERCENTAGE  OF  RUN-OFF  FROM  THE  SAVANNAH,  CONNECTICUT,  AND 

POTOMAC  RIVER  BASINS 


Basin 

Time 

Percentage  of 
rainfall  carried 
off  in  drainage 

Savannah  river    ...    

1884  to  1891 

48.9 

Connecticut  river    :  

13  years 

56.5 

Potomac  river  

1886  to  1891 

53.0 

It  has  been  estimated  that  for  broad  valleys  and  gentle  slopes  in 
open  country,  a  mean  annual  rainfall  of  50  inches  gives  an  annual 
run-off  of  about  25  inches,  or  50  percent  of  the  total  rainfall.  Where 
the  rainfall  is  40  inches,  the  run-off  is  about  15  inches,  or  37.5  percent ; 
and  where  the  rainfall  is  30  inches,  the  run-off  is  about  8  inches,  or  26.6 
percent.  Greenleaf  estimates  the  average  run-off  for  the  Illinois  river 
basin  at  about  24  percent  of  the  total  rainfall  of  the  catchment  area. 
Leverett  estimates  the  run-off  for  the  entire  state  of  Illinois  at  about 
21  percent  of  the  rainfall. 

The  work  of  the  Illinois  State  Geological  Survey  shows  that  the 
run-off  for  the  Spoon  river  basin  is  21.5  percent  of  the  total  rainfall ; 
for  the  Embarrass  river  basin,  25  percent ;  and  for  the  Kaskaskia,  37.9 
percent.  Table  4  will  be  of  interest  as  showing  the  run-off  in  the 
Kaskaskia  river  basin  for  the  years  1907  to  1909.  The  very  high 

TABLE  4. — RAINFALL  AND  RUN-OFF  IN  THE  KASKASKIA  RIVER  BASIN,  1907-1909 


1907 

1<M)8 

1909 

Average 

Rainfall,  inches  

41.80 

38  22 

48  48 

42  8 

Run-off,  inches  

13.52 

19  20 

15  07 

15  9 

Percentage  of  rainfall  lost  as  run-off 

32.34 

50.23 

31.08 

37.9 

run-off  in  1908  was  due  to  the  extremely  heavy  rainfall  during  Feb- 
ruary, April,  and  May,  when  it  amounted  to  19.57  inches,  or  more 
than  the  total  for  the  rest  of  the  year.  The  rainfall  during  May  alone 
was  9.55  inches,  or  25  percent  of  the  total  for  the  year. 


W]8]  WASHING  OP  SOILS  AND  METHODS  OP  PREVENTION  519 

If  the  Illinois  river  basin,  with  its  extensive  areas  of  level  to  gently 
rolling  land,'  has  a  run-off  amounting  to  24  percent  of  the  annual 
rainfall,  it  is  certainly  conservative  to  say  that  the  hilly  and  broken 
land  of  the  state  with  perfect  surface  drainage  and  slowly  pervious 
soil,  suffers  at  least  twice  as  much  loss  of  water. 

WORK  OF  MOVING  WATER 

If  a  current  of  water  with  a  given  velocity  is  capable  of  causing  a 
certain  amount  of  erosion,  it  will  be  able  to  do  four  times  as  much 
work  if  the  velocity  of  the  current  is  doubled.  If  it  is  able  to  carry 
a  certain  amount  of  material  at  a  given  velocity,  it  will  be  capable  of 
carrying  thirty-two  times  as  much  with  a  doubled  velocity.  If  a 
slowly  moving  stream  carries  particles  of  a  certain  size,  it  will  carry 
particles  sixty-four  times  as  large  when  the  velocity  is  twice  as  great. 
When  a  solid  is  immersed  in  water  it  loses  weight  equal  to  the  weight 
of  the  water  displaced  by  it,  thus  making  the  material  relatively  lighter 
in  water  than  in  air,  and  consequently  more  easily  moved. 

Considering  the  above  laws  of  physics,  it  will  be  seen  how  power- 
ful an  agent  is  moving  water  for  loosening  and  carrying  away  soil 
material. 

Since  the  destructive  work  of  water  upon  soil  depends  directly 
upon  the  amount  and  velocity  of  the  water  running  over  the  surface, 
protective  and  preventive  measures  should,  as  a  rule,  include  methods 
for  diminishing  the  amount  and  Velocity  of  the  run-off. 

KINDS  OF  EROSION 

The  erosion  produced'  by  run-off  is  of  two  kinds:  (1)  sheet 
erosion,  or  general  surface  washing;  and  (2)  gullying,  of  which  there 
are  two  phases — head-water  erosion  and  waterfall  erosion. 

In  sheet  erosion,  the  water  moves  over  a  uniformly  sloping  sur- 
face, and  if  the  soil  and  vegetative  covering  are  uniform,  the  amount 
of  material  removed  will  be  practically  the  same  for  all  points.  This 
form  of  washing  results  in  the  removal  of  the  surface  soil  and  in  the 
gradual  reduction  of  fertility.  It  occurs  to  a  greater  or  less  extent 
in  practically  every  field. 

Ordinarily,  however,  the  process  of  washing  is  not  so  simple  as 
this.  More  frequently  the  slope  is  not  uniform,  but  contains  small  draws 
in  which  the  water  collects,  giving  to  the  run-off  greater  velocity 
and  consequently  greater  erosive  power.  The  water  flowing  in  these 
draws  soon  forms  a  gully.  The  effect  at  first  is  usually  greatest  to- 
ward the  lower  end  of  the  draw,  because  of  the  larger  volume  of  water. 
Eventually,  however,  the  eroding  action  of  the  water  increases  the 
steepness  of  the  upper  part  of  the  slope,  so  that  even  with  a  smaller 


520 


BULLETIN  No.  207 


[April, 


volume  of  water  a  large  amount  of  work  is  done,  and  the  gully  gradu- 
ally eats  its  way  up  the  slope  by  what  is  called  head-water  erosion. 

A  draw  is  not  always  necessary  for  the  beginning  of  gullies,  but 
there  must  be  something  to  give  direction  to  the  water.    On  uniform 
slopes  they  may  be  started  by  very  simple  agencies.    Tunnels  made ' 
by  moles,  the  tracks  of  wagon  wheels,  or  paths  made  by  cows,  pigs, 
or  sheep  may  afford  the  small  beginning — and  nature  wrill  do  the  rest. 

The  waterfall  type  of  erosion  occurs  where  the  surface  material 
to  a  depth  of  two  to  four  feet  is  more  resistant  than  that  beneath.  If 
by  any  means  a  waterfall  should  start,  as  is  often  the  case  where  water 
runs  into  a  ditch  or  ravine,  the  undermining  action  of  the  water  as  it 
falls  over  the  low  precipice  causes  masses  of  the  surface  to  break  off 
and  fall  into  the  gully.  This  loosened  material  is  carried  away  and  the 
process  repeated.  By  this  means  the  waterfall  slowly  moves  up  the 
slope,  leaving  a  narrow  gully  with  very  steep  sides.  The  waterfall 
may  vary  from  three  to  twenty  feet  in  height,  but  it  is  usually  four 
to  six  feet. 

These  waterfalls  are  most  apt  to  occur  in  meadows  and  pastures 
where  the  grass  roots  make  a  resistant  surface,  altho  any  soil  underlain 
by  loose,  incoherent  material  may  erode  in  this  way  regardless  of 
the  method  of  cropping.  The  unprotected  outlet  of  a  tile  ditch  may 


FIG.  5. — HEAD  OF  GORGE  SHOWN  IN  FIG.  6 

Note  the  condition  of  the  tile  outlet.    The  water  undermines  the  tile  by  carry- 
ng  away  the  incoherent  sand  at  -(-. 


1018} 


WASHING  OF  SOILS  AND  METHODS  or  PREVENTION 


521 


furnish  the  necessary  beginning,  especially  where  the  water  at  the 
end  of  the  tile  has  a  drop  of  several  feet  (see  Figs.  5  and  6).  Fig.  7 
shows  a  well-protected  tile  outlet. 


FIG.  6. — A  GORGE  IN  MASON  COUNTY 


This  gorge  started  about  twenty  years  ago  from  a  neglected  tilo  outlet.  The 
water  from  the  tile  washed  a  ditch,  slowly  undermined  the  end  of  the  tile,  and 
backed  up  about  30  rodsj  forming  a  gorge  from  40  to  50  feet  deep.  At  the  head 
of  this  gorge  the  tile  branched,  and  two>  gorges  started.  One  of  these  is  now 
30  rods  long,  from  50  to  70  feet  wide,  and  from  23  to  35  feet  deep.  A  concrete 
dam  has  been  placed  near  its  head  to  stop  further  encroachment  (Fig.  26).  The 
other  gorge  has  extended  about  40  rods  and  is  from  30  to  50  feet  wide  and  from 
20  to  30  feet  deep.  Near  the  end  of  this  gorge  the  tile  again  branches,  and  two 
gorges  are  starting;  these  have  advanced  4  to  6  rods  along  the  tiles.  At  a  depth 
of  4  to  8  feet  there  is  a  stratum  of  fine,  incoherent  sand,  which  washes  out  very 
readily,  allowing  the  unsupported  surface  to  cave  in  (Fig.  5). 


522  BULLETIN  No.  207  [April, 

EFFECTS  OF  EROSION 
Loss  OF  ORGANIC  MATTER,  NITROGEN,  AND  PHOSPHORUS 

Nothing  will  completely  ruin  land  more  quickly  than  erosion, 
especially  gullying.  A  great  many  fields  have  already  been  abandoned 
from  this  cause.  A  single  season  or  even  a  single  rain  may  produce 
gullies  that  cannot  be  crossed  with  ordinary  farm  implements.  Unless 
erosion  is  practically  stopped,  the  land  soon  becomes  almost  worthless 
(see  Fig.  9). 

While  sheet  washing  may  not  ruin  land  so  quickly  and  so  com- 
pletely as  gullying,  yet  much  more  damage  is  done  by  it  because  it 
occurs  over  a  much  greater  area.  This  type  of  erosion  takes  place  to  a 
damaging  extent  on  the  undulating  land,  and  to  a  greater  extent  upon 
the  more  rolling  and  hilly  lands.  Prairie  soils  are  not  subject  to  so 
much  erosion  as  timber  soils,  since  their  higher  organic-matter  content 
protects  them  to  a  considerable  degree. 

The  first  effect  of  erosion  is  to  remove  the  surface  soil.  Since 
this  commonly  contains  a  larger  supply  of  organic  matter,  nitrogen, 
and  phosphorus  than  any  other  stratum,  its  removal  naturally  lowers 
the  plant-food  content  in  the  type  of  soil  most  subject  to  erosion,  and 
increases  it  in  the  one  receiving  the  wash. 

Hilly  timber  land  is  naturally  deficient  in  organic  matter,  and 
after  it  has  been  cleared  and  cultivated  the  run-off  soon  removes  a  very 
large  part  of  the  surface  soil  and  along  with  it  the  organic  matter 
and  the  two  most  important  elements  of  plant  food,  nitrogen  and 
phosphorus.  It  should  be  noted,  however,  that  soils  naturally  subject 
to  erosion,  such  as  yellow  silt  loam,  may  contain  as  much  or  even 


FIG.  7.— A  WELL-PROTECTED  TILE  OUTLET. 


1918} 


WASHING  OF  SOILS  AND  METHODS  OF  PREVENTION 


523 


FIG.  8. — WATERFALL  EROSION  ON  PASTURE  LAND  IN  OGLE  COUNTY 


FIG.  9.— EFFECTS  OF  SHEET  WASHING,  PIKE  COUNTY 

more  phosphorus  in  the  subsoil  or  the  subsurface  than  in  the  surface, 
even  when  equal  weights  are  considered. 

Table  5  shows  the  amount  of  organic  matter,  nitrogen,  and  phos- 
phorus in  the  surface  stratum  of  each  of  the  two  representative  timber 
soils  in  the  state  and  'of  the  bottom  land  receiving  their  wash.  Yel- 
low-gray silt  loam  has  not  suffered  much  from  washing,  but  yellow 
silt  loam  is  generally  badly  eroded.  The  abandoned  land  is  usually 
of  this  latter  type.  The  bottom  land  receives  much  sediment  from  the 
yellow-gray  silt  loam  areas  and  some  from  other  less  rolling  types, 
but  it  receives  perhaps  even  more  from  the  yellow  silt  loam. 


524 


BULLETIN   NO.   207 


[April, 


TABLE  5. — ORGANIC  MATTER,  NITROGEN,  AND  PHOSPHORUS   IN  THE   SURFACE 
M  OP  REPRESENTATIVE  TIMBER  SOILS  AND  THE  BOTTOM 

LAND  RECEIVING  THEIR  WASH 
2  million  pounds  of  surface  soil  per  acre  (0-6%  inches) 


County 

Yellow-gray  silt  loam 
(undulating) 

Yellow  silt  loam 
(hilly) 

Bottom  land 
(small  streams) 

OM 

N 

P 

OM 

N 

P 

OM 

N 

P 

Bond  

tons 
22.8 
16.9 
13.4 
26.9 
22.4 
27.8 
28.1 
26.7 
29.0 
24.3 
22.6 
22.6 
20.1 
19.6 

/6s. 
2530 
1  650 
1  520 
2710 
2440 
2720 
2527 
2620 
2940 
2310 
2  120 
2300 
2020 
2  200 

/6s. 
470 
550 
870 
810 
860 
750 
1033 
880 
1  050 
680 
780 
1  010 
850 
870 

tons 
19.1 
14.7 
11.0 
20.7 
21.9 
18.1 
20.7 
18.4 
15.3 
16.6 
14.8 
8.8 
15.3 
24.8 

/6s. 
2068 
1  540 
1  250 
2040 
2330 
1  880 
2093 
2  140 
1  650 
1  580 
1  590 
920 
1  710 
2480 

/6s. 
696 
510 
840 
720 
820 
720 
773 
830 
750 
480 
730 
820 
840 
910 

tons 
25.4 
25.1 
11.6 
97.1 
52.4 
77.1 
36.7 
40.5 
62.8 
28.6 
34.8 
44.0 
35.9 
63.1 

/6s. 
2605 
2805 
1  195 
9020 
4910 
8  190 
4440 
4580 
6300 
3390 
3230 
4450 
3820 
6770 

/6s. 
1  370 
1  050 
615 
1  560 
1  790 
1  490 
1  260 
1  740 
1  940 
940 
1  150 
1  630 
1  255 
1860 

Clay.  . 

Hardin  .  .  . 

Kankakee 

Knox  

Lake.  ... 

LaSalle  

McDonough  .  .  . 
McLean  

Moultrie  

Pike  

Sangamon   .... 

Tazewell  

Winnebago    .  .  . 

Average  

23.1 

2330 

819 

17.1 

1  805 

746 

45.3; 

4693 

1403 

This  table  shows  that  in  the  surface  6%  inches  yellow-gray  silt 
loam  contains  an  average  of  23.1  tons  of  organic  matter  per  acre; 
yellow  silt  loam,  17.1  tons  ;  and  the  bottom  land,  45.3  tons.  The  nitro- 
gen and  phosphorus  content  in  the  surface  soil  of  these  three  types 
varies  in  this  same  order,  the  types  containing  respectively  2,330,  1,805, 
and  4,693  pounds  of  nitrogen;  and  819,  746,  and  1,403  pounds  of 
phosphorus  per  acre.  A  nitrogen  content  of  only  1,805  pounds  per 


TABLE  6.  —  ORGANIC  MATTER,  NITROGEN,  AND  PHOSPHORUS  IN  THE 

STRATUM  OF  REPRESENTATIVE  TIMBER  SOILS 
4  million  pounds  of  subsurface  soil  per  acre  (6%  -  20  inches) 


County 

Yellow-gray  silt  loam 
(undulating) 

Yellow  silt  loam 
(hilly) 

OM 

N 

P 

OM 

N 

P 

Bond  

tons 
18.2 
11.8 
11.7 
20.7 
14.5 
22.6 
20.7 
15.0 
19.3 
15.1 
24.5 
14.5 
12.9 
14  0 

/6s. 
2600 
1  520 
1  500 
2710 
2210 
2630 
2280 
2  150 
2710 
2040 
2  140 
2  150 
2090 
2220 

Ibs. 
1340 
860 
1820 
1280 
1420 
1  300 
1  907 
1  420 
1  490 
1  100 
1  370 
1  760 
1  580 
1  820 

tons 
14.7 
13.6 
8.2 
17.4 
14.7 
20.7 
15.5 
11.5 
13.1 
14.8 
12.6 
11.5 
11.7 
25.9 

/6s. 
2  120 
1  830 
1390 
2  160 
1  870 
2720 
2280 
1960 
2020 
1  720 
1  600 
1540 
1  650 
2980 

/6s. 
1  270 
790 
1  930 
1  400 
1  610 
1  620 
1  387 
1  700 
1  540 
1  200 
1  560 
1880 
1  670 
2  180 

Clay  

Hardin  

Kankakee  

Knox  

Lake  

LaSalle  

McDonough  

McLean  

Moultrie  

Pike  

Sangamon  

Tazewell  

Winnebago  

Average  

16.8 

2210 

1462 

14.7 

1  990 

1553 

Idl8\  WASHING  OP  SOILS  AND  METHODS  OP  PREVENTION  525 

acre  is  not  sufficient  to  produce  profitable  crops.  If  that  amount  is 
not  a  sufficient  reserve  from  which  to  grow  fair  and  profitable  crops, 
what  can  be  expected  from  a  soil  whose  nitrogen  content  has  been  re- 
duced by  washing  to  one-half  the  above  amount,  a  condition  which  is 
produced  when  the  surface  soil  is  removed  by  erosion  (see  Table  6). 
In  comparing  the  figures  in  Table  5  and  Table  6,  it  will  be  well  to 
remember  that  the  subsurface  stratum  is  twice  the  thickness  of  the 
surface  layer ;  so  that  in  the  subsurface  of  yellow  silt  loam,  for  example, 
there  are  but  995  pounds  of  nitrogen  in  a  stratum  of  the  same  thick- 
ness as  the  surface  stratum. 

CHANGES  IN  THE  PHYSICAL  CHARACTER  OF  THE  SOIL 

Two  distinct  changes  in  the  physical  character  of  the  soil  are 
produced  by  erosion:  first,  a  change  in  color;  and  second,  a  change 
in  the  physical  composition,  or  texture. 

The  surface  soil  of  the  rolling  timber  types  has  a  brownish  yellow 
color,  owing  to  the  mixture  of  organic  matter  and  iron  oxid.  When 
erosion  takes  place,  the  yellow  or.  reddish  yellow  subsurface  or  subsoil 
is  exposed.  The  effect  is  to  slightly  reduce  the  temperature  of  the 
soil,  since  yellow  soils  do  not  absorb  heat  so  readily  as  the  darker 
colored  soils. 

The  most  important  change  in  physical  character  is  that  of  tex- 
ture. The  surface  soil  is  usually  a  mealy,  friable,  silt  loam,  easy  to 
work.  The  subsoil  is  often  a  somewhat  tenacious,  yellow  clayey  silt 
or  silty  clay,  and  when  this  is  exposed  by  erosion  it  forms  a  soil  that 
is  very  difficult  to  plow  and  still  more  difficult  to  reduce  to  a  condition 
of  good  tilth  for  a  seed  bed.  The  physical  condition  of  this  subsoil 
renders  it  a  slow  absorbent  of  water,  so  that  the  run-off  is  actually 
increased  by  erosion. 


526  BULLETIN  No.  207  '[April, 


METHODS  OF  REDUCING  EROSION 

It  would  commonly  be  taken  for  granted  that  the  thing  of  first 
importance  in  reducing  erosion  is  the  preventing  of  the  formation 
of  gullies  in  cultivated  fields,  but  this  is  not  the  case.  The  beginning  of 
the  trouble  is  usually  due  to  sheet  washing,  and  as  a  rule  gullying 
occurs  in  the  later  stages  of  the  general  process  of  land  ruin.  If  we 
can  prevent  sheet  washing,  we  shall  very  largely  lessen  gullying  in 
cultivated  fields. 

REDUCING  SHEET  WASHING 

Five  general  methods  are  employed  for  the  prevention  of  sheet 
washing:  (1)  growing  cover  crops,  in  order  to  decrease  the  move- 
ment of  water  and  soil;  (2)  increasing  the  organic-matter  content,  in 
order  to  bind  the  soil  particles  together;  (3)  using  methods  of  tillage 
which  will  check  the  velocity  of-  the  run-off  and  cause  greater  absorp- 
tion; (4)  tiling  in  order  to  increase  the  porosity  of  the  soil  and  con- 
duct the  water  thru  safe  channels;  and  (5)  constructing  terraces  and 
embankments  which  encourage  the  absorption  of  the  rainfall  or  so 
modify  the  slope  of  the  land  as  to  conduct  the  surplus  water  off  at 
a  grade  that  will  cause  little  or  no  washing. 

1.  Cover  Crops. — In  the  management  of  rolling  land,  a  rota- 
tion should  be  adopted  that  will  keep  the  land  in  pasture  and  meadow 
during  a  large  part  of  the  time,  or  that  will  at  least  keep  a  covering  of 
vegetation  on  the  soil  as  much  of  the  time  as  possible.  Before  these 
rolling  and  hilly  lands  were  brought  under  cultivation,  they  were 
largely  covered  with  vegetation  of  some  form.  The  leaves  of  trees 
and  fallen  branches,  together  with  the  smaller  plants,  formed  a  cov- 
ering that  did  much  to  prevent  the  soil  from  washing.  The  rainfall 
was  held  by  the  layer  of  leaves  and  mold,  and  the  water  was  allowed  to 
pass  off  slowly  to  the  streams.  But  as  soon  as  the  protecting  forest 
was  removed,  the  water  ran  off  in  a  flood  almost  as  soon  as  it  fell. 
The  upland  timber  soils  of  the  state  were  usually  in  poor  physical 
condition  when  first  put  under  cultivation,  or  became  so  after  a  few 
years  of  cropping,  and  consequently  percolation  is  comparatively  slow. 

If  a  cultivated  crop  is  grown,  such  as  corn,  a  cover  crop  should 
be  put  in  just  before  or  after  the  last  cultivation,  to  protect  the  soil 
from  washing  during  the  fall,  winter,  and  spring.  Rye  is  one  of  the 
best  cover  crops  for  this  purpose  because  it  lives  thru  the  winter 
and  makes  a  fair  growth  of  top  and  an  abundance  of  fine,  fibrous  roots 
that  hold  the  soil  particles  in  place.  It  may  be  left  for  green  manure 
or  pasture  in  the  spring.  A  mixture  of  lye  and  sweet  clover  may  prove 
better  than  rye  alone. 


WASHING  OF  SOILS  AND  METHODS  OF  PREVENTION 


527 


Cowpeas  may  be  used  as  a  cover  crop  with  fair  success,  especially 
in  the  southern  part  of  the  state,  but  they  do  not  have  the  binding 
power  of  rye  and  are  killed  by  frost.  The  clovers,  either  sweet,  red,  or 
alsike,  may  make  sufficient  growth  during  favorable  seasons  to  protect 
the  soil  during  the  winter  and  spring,  but  they  are  not  so  sure  as  rye 
unless  the  soil  is  treated  or  especially  adapted  to  them.  Besides,  much 
of  this  rolling  land  in  southern  Illinois  is  sour  and  must  be  sweetened 
with  ground  limestone  before  clover  will  do  its  best. 

As  already  stated,  thesa  legumes,  aside  from  their  value  as  cover 
crops,  are  also  very  beneficial  to  the  soil  for  the  nitrogen  they  supply. 
The  clover  may  be  left  and  turned  under  as  a  green  manure  in  time 
to  plant  another  crop,  such  as  corn,  or  it  may  be  harvested  or  pastured, 
or,  what  is  better  still  from  the  standpoint  of  soil  improvement,  the 
entire  crop  may  be  turned  under.  It  must  always  be  borne  in  mind, 
however,  that  a  large  growth  of  clover  removes  a  very  large  amount 
of  moisture  from  the  soil,  and  when  turned  under  as  green  manure  in 
dry  seasons  it  may  leave  the  soil  so  dry  that  the  succeeding  crop  will 
suffer. 

In  general,  any  crop  may  be  grown  as  a  cover  crop  that  will 
furnish  sufficient  material  both  of  top  and  roots  to  hold  the  soil  in 
place.  The  seeding  of  rye  and  timothy  in  the  fall,  with  red  clover  and 
alsike  in  the  spring,  followed  by  pasturing,  is  one  of  the  very  best 
methods  of  treatment.  Crab  grass  in  corn  may  make  a  good  cover 
also. 

Much  of  the  rolling  and  hilly  land  of  the  state  should  be  kept  in 
permanent  blue-grass  pasture  (see  Fig.  10).  If  sweet,  alsike,  or  white 
clover  can  be  grown  along  with  the  blue  grass,  much  better  results  will 
be  obtained.  The  binding  power  of  blue-grass  roots  is  very  great, 
and  gullying  is  almost  entirely  prevented  except  when  waterfalls  start 


FIG.  10. — A  GOOD  WAY  TO  MANAGE  HILLY  LAND  is  TO  KEEP  IT  IN  PERMANENT 

BLUE-GRASS  PASTURE 


528  BULLETIN  No.  207  [April, 

(see  Fig.  8)  and  gullies  advance  by  head-water  erosion.  If  blue  grass 
only  is  grown,  the  soil  becomes  very  compact,  so  that  comparatively 
little  rainfall  will  be  absorbed.  At  most,  the  amount  absorbed  is 
small.  Clovers,  and  particularly  sweet  clover,  with  its  deep  roots, 
loosen  the  soil,  keeping  it  in  good  condition.  Besides,  the  clovers 
furnish  nitrogen  for  the  grass. 

2.  Increasing  the  Organic-Matter  Content. — In  the  management 
of  the  soils  of  rolling  land,  it  is  important  to.  add  organic  matter,  not 
only  because  of  the  effect  it  has  in  preventing  washing  and  in  pro- 
ducing good  tilth,  but  also  because  it  increases  the  moisture  capacity, 
conserves  the  moisture,  aids  ventilation,  and  furnishes  a  supply  of 
nitrogen  for  the  plant  (see  Fig.  11).  One  of  the  effects  of  organic 


FIG.  11. — WHEAT  AFTER  CLOVER 

Farm  of  A.  P.  Schroeder,  Pulaski  county.     Showing  possibilities  of  production 
on  rolling  land. 

matter  on  a  soil  is  to  keep  it  loose  and  porous  by  forming  granules.  In 
this  condition  the  soil  will  readily  absorb  water  and  the  run-off  will 
be  greatly  reduced.  A  granular  soil  will  not  erode  to  any  considerable 
extent,  not  only  because  there  is  less  run-off,  but  also  because  the  gran- 
ules are  too  large  to  be  moved  readily  by  water.  The  organic  matter 
also  prevents  to  a  large  extent  the  formation  of  impervious  crusts  by 
beating  rains. 

The  amount  of  organic  matter  naturally  present  in  the  soil  varies 
quite  widely  with  the  type  of  soil.  In  general,  the  upland  timber 
soils  of  the  state  have  much  less  organic  matter  than  the  prairie  types. 
The  chief  reason  for  this  is  the  fact  that  in  the  prairie  soils  the  roots 
of  the  grasses  which  once  covered  them,  being  protected  by  the  moist 


1H18] 


WASHING  OF  SOILS  AND  METHODS  OP  PREVENTION 


529 


soil,  underwent  only  partial  decay,  while  in  the  forest  the  leaves  of 
the  trees  falling  upon  the  surface  of  the  ground  were  exposed  to  com- 
plete decay  or  to  destruction  by  forest  fires.  Table  7  gives  the  amount 
of  organic  matter  in  the  surface  and  subsurface  strata  of  the  principal 
types  of  timber  and  prairie  soils  of  the  state  at  the  present  time, 
calculated  from  the  total  amount  of  organic  carbon  found. 

TABLE  7. — AMOUNT  OP  ORGANIC  MATTER  IN  THE  PRINCIPAL  TIMBER  AND 

PRAIRIE  SOILS  OF  ILLINOIS 
(Surface  2  million  pounds,  subsurface  4  million  pounds  per  acre) 


Area  and  county 

^Tim 

bcr£&~Jjf 

0_^jTPr 

iirie^*2'la 

(M  ^p* 

*.'••[     U|J|   flllll 

o       f 

d    i,         e 

rauriUiCC 

sunacc 

Unglaciated  : 
Hardin  

tons 
12.6 

tons 
10  4 

tons 

tons 

Johnson  

17.1 

13.1 

Average  

14.8 

11.8 

Lower  Illinoisan: 
Bond  

19.9 

12.4 

26.0 

26.6 

Clay  ' 

15.4 

10.9 

22.9 

29.8 

Average  

17.6 

11.6 

24.5 

28.2 

Middle  Illinoisan: 
Sangamon  

15.7 

16.8 

44.0 

52.2 

Upper  Illinoisan  ' 
Knox  

22.3 

15.5 

58.1 

66  0 

McDonough  

27.2 

11.7 

50.0 

59.2 

Pike  

18.9 

17.9 

31.5 

46.2 

Average  

22.8  . 

15.0 

46.5 

57.1 

Early  Wisconsin: 
LaSalle  

24.4 

18.0 

52.0 

47.7 

McLean  

22  2 

17.1 

50.7 

54.6 

Moultrie  .  

19  3 

14.8 

50.9 

48.4 

Tazewell  

17.5 

12.1 

57.9 

62.7 

Average  

20.8 

15.5 

52.9 

53.4 

Late  Wisconsin  : 
DuPage             .  . 

22  4 

18.7 

65.3 

47.6 

Lake  

19.8 

17.0 

77.5 

78.5 

Average  

21.1 

17.8 

71.4 

63.1 

To  show  the  value  of  legumes  on  soils  subject  to  erosion,  the 
results  obtained  in  some  pot-culture  experiments  at  the  University  of 
Illinois  are  presented.  A  soil  taken  from  the  washed  hill  land  in 
Pulaski  county  was  placed  in  pots,  and  different  elements  of  plant 
food  were  added  to  all  except  one  pot,  which  served  as  a  check.  Fig. 
12  shows  the  difference  in  growth  due  to  the  different  methods  of  treat- 
ment. Wheat  was  grown  the  first  four  years,  after  which  wheat  and 
oats  were  grown  in  alternate  years.  In  Pots  A2,  All,  and  A12,  after 


530 


BULLETIN  No.  207 


[April, 


FIG.  12. — EFFECT  OF  NITROGEN  AS  SUPPLIED  BY  LEGUMES  OB  IN  COMMERCIAL  FORM 

the  wheat  and  oats  had  been  harvested,  cowpeas  were  seeded  and 
turned  under  for  the  crop  following.  The  yields  obtained  under  the 
various  treatments  are  shown  in  Table  8. 

It  must  be  remembered  that  these  yields  were  obtained  in  the 
greenhouse  under  conditions  much  more  'favorable  than  are  ordinarily 
found  in  the  field.  It  is  interesting  to  note  that  the  average  yields 
without  treatment  were  9.0  bushels  of  wheat  and  41.5  bushels  of  oats 


TABLE  8. — CROP  YIELDS  IN  POT-CULTURE  EXPERIMENT  WITH  YELLOW  SILT  LOAM 

OP  WORN  HILL  LAND  AND  NITROGEN-FIXING  GREEN-MANURE  CROPS 

(Grams  per  pot) 


Pot  No. 

Al 

A2 

All 

A12 

A3 

A6 

A9 

A8 

Treatment 

• 

None 

LLe  ' 

LLeP 

LLe 
PK 

LN 

LNP 

LNPK 

LPK 

I90;i 

Wheat 

5.0 

10.0 

14.0 

10.0 

17.0 

2(3.0 

31.0 

3.0 

1904 

Wheat 

4.0 

17.0 

19.0 

20.0 

14.0 

20.0 

34.0 

3.0 

1905 

Wheat 

4.0 

26.0 

20.0 

21.0 

15.0 

18.0 

21.0 

5.0 

1906 

Wheat 

4.0 

19.0 

18.0 

19.0 

9.0 

18.0 

20.0 

3.0 

1907 

Oats 

6.0 

37.0 

27.0 

30.0 

28.0 

30.0 

26.0 

7.0 

1908 

Wheat 

4.0 

16.3 

10.2 

16.0 

13.0 

3.6 

7.7 

3.5 

1909 

Oats 

10.2 

27.2 

24.2 

34.6 

27.4 

66.8 

51.8 

10.2 

1910 

Wheat 

2.1 

15.3 

20.0 

32.8 

21.0 

37.4 

31.4 

4.1 

1911 

Oats 

6.4 

11.1 

20.6 

24.2 

32.8 

38.4 

39.5 

6.1 

1912 

Wheat 

0.1 

19.  a 

18.4 

25.9 

25.9 

25.9 

23.8 

4.1 

1913 

Oats 

6.2 

26.2 

22.2 

24.5 

27.6 

30.8 

21.6 

7.0 

1914 

Wheat 

0.3 

19.9 

15.6 

21.6 

12.2 

13.1 

9.7 

5.2 

1915 

Oats 

12.7 

24.0 

25.1 

22.9 

21.3 

16.6 

17.3 

15.5 

1916 

Wheat 

7.0 

14.2 

10.2 

17.5 

13.7 

7.2 

11.4 

4.3 

Average  of 

9  years 

Wheat 

3.4 

17.4 

16.2 

21.1 

15.6 

18.8 

21.1 

3.9 

Average  of 

• 

5  years 

Oats 

8.3 

25.1 

23.8 

27.2 

27.4 

36.5 

31.2 

9.2 

Yield  Calculated  to  Acre  Basis  (Bushels) 


Wheat  

9  0 

46  4 

43  2 

56  3 

41  6 

50  1 

56  3 

10  4 

Oats  

41.5 

125.5 

191.1 

136.2 

137.1 

182.6 

156.2 

45.8 

NOTE. — L=limestone;   L3=legume;   P= phosphorus;   K— potassium    (kalium) 
N=nitrogen. 


1918} 


WASHING  OF  SOILS  AND  METHODS  OF  PREVENTION 


531 


.per  acre,  and  with  lime,  phosphorus,  and  potassium  added  they  were 
10.4  and  45.8  bushels  respectively ;  that  with  lime  and  legumes  added, 
the  yields  were  46.4  bushels  of  wheat  and  125.5  of  oats;  while  with 
lime  and  nitrogen  (dried  blood),  they  were  41.6  bushels  of  wheat  and 
137.1  bushels-  of  oats ;  and  that  the  average  of  all  pots  receiving  nitro- 
gen and  other  plant  food  was  49.0  bushels  of  wheat  and  154.8  bushels 
of  oats. 

The  experiment  certainly  demonstrates  the  fact  that  soils  sub- 
ject to  erosion  need  nitrogen;  and  one  of  the  great  problems  of  the 
farmer  on  this  kind  of  land  is  not  only  to  maintain  but  to  increase 
the  supply  of  nitrogen  in  the  soil.  The  most  practical  way  of  doing 
this  on  an  extensive  scale  is  to  add  organic  matter  by  turning  under 
legumes  and  manure,  ground  limestone  being  used  as  needed  to  cor- 
rect acidity  (see  Bulletin  115  of  this  station). 

To  increase  the  organic  matter  in  soils,  it  is  necessary  to  utilize 
all  the  vegetable  matter  produced.  Farm  manure  should  be  turned 
back  into  the  soil  as  soon  as  possible.  Too  often  it  is  left  piled  up 
against  the  barn,  where  it  rots  the  boards  and  where  much  of  the 
most  valuable  part  of  it  leaches  away.  Weeds,  stubble,  and  corn  stalks 
should  be  plowed  under  instead  of  being  burned,  as  is  so  frequently 
done.  Crops  of  rye,  or  preferably  legumes,  should  be  grown  and 
turned  under ;  they  will  not  only  increase  the  organic-matter  content, 
but  at  the  same  time  augment  the  scanty  supply  of  nitrogen  in  these 


FIG.  13. — COWPEAS  ON  SERIES  C,  UNIVERSITY  OF  ILLINOIS  EXPERIMENT  FIELD 

AT  VIENNA 

When  turned,  under,  the  cowpeas  materially  increase  the  nitrogen  and  organic- 
matter  content  of  the  soil. 


532 


BULLETIN  No.  207 


[April, 


soils  (see  Fig.  13).  A  crop  of  cowpeas  or  clover  is  not  wasted  if 
plowed  under;  the  increased  yield  of  the  succeeding  crops  may  more 
than  pay  for  it.  The  turning  under  of  cover  crops  will  help  to  increase 
the  supply  of  organic  matter,  but  this  is  too  slow  a  process  on  land  that 
is  washing  badly;  one  or  two  entire  crops  in  a  four-year  rotation 
should  be  plowed  under  until  the  supply  is  materially  increased. 

Sweet  clover  is  one  of  the  best  crops  to  grow  for  the  improvement 
of  eroded  land  (see  Fig.  14)  for  the  following  reasons:  (1)  a  surer 
and  better  catch  may  be  obtained  with  it  than  with  red  clover;  (2) 
its  very  deep-rooting  nature  and  large  growth  makes  it  most  valuable 
for  soil  renovation;  (3)  it  will  grow  on  almost  any  kind  of  soil, 
whether  badly  eroded,  good,  or  stony,  the  only  necessary  conditions 
being  the  presence  of  limestone  and  the  proper  bacteria;  (4)  it  will 
furnish  a  large  amount  of  excellent  feed  in  the  form  of  pasture  or 
hay;  (5)  it  possesses  a  feeding  value  as  high  as  that  of  red  clover; 
(6)  it  is  one  of  our  best  honey-producing  plants ;  (7)  it  will  likely  be  a 
money  crop  because  of  the  amount  of  seed  it  produces  and  the  price 
the  seed  brings. 

All  forms  of  organic  matter  are  about  equally  important  to  the 
soil  from  a  physical  standpoint,  yet  legumes  are  much  more  valuable 
than  other  plants  because  of  the  large  amount  of  nitrogen  which  they 
contain.  A  ton  of  corn  stalks  contains  16  pounds  of  nitrogen;  oat 
straw,  12  pounds;  wheat  straw,  10  pounds;  clover,  40  pounds;  cow- 
peas,  43  pounds ;  and  sweet  clover,  about  40  pounds.  A  50-bushel  crop 


FIG.  14. — SWEET  CLOVER  ON  THE  VIENNA  EXPERIMENT  FIELD 
Growth  during  the  first  season  (seeded  in  March), 


WASHING  OF  SOILS  AND  METHODS  on1  PREVENTION  533 

of  corn  requires  for  its  production  75  pounds  of  nitrogen.  To  provide 
this  nitrogen,  about  1,500  pounds  of  average  soil  humus  must  be  de- 
composed and  lost  to  the  soil.  If  the  average  amount  of  humus  in  the 
surface  seven  inches  is  2  percent,  or  20  tons  per  acre,  it  would  require 
only  twenty-seven  50-bushcl  crops  of  corn  to  completely  exhaust  the 
supply  of  soil  humus ;  from  which  it  may  be  seen  that  even  if  a  soil 
has  a  good  store  of  organic  matter  to  begin  with,  it  does  not  require  a 
great  many  years  of  cropping  to  reduce  the  supply  below  what  it 
should  be.  This  rapid  depletion  of  organic  matter  is  hastened  mate- 
rially by  washing,  and  it  soon  reduces  the  soil  to  a  condition  of  unpro- 
ductiveness. The  more  a  soil  is  ' '  run  down, ' '  the  more  difficult  it  is  to 
grow  clovers  or  other  soil-renovating  crops.  (See  Bulletin  115.) 

3.  Tillage. — Probably  nothing  that  can  be  done  to  rolling  land 
damages  it  more  seriously  than  faulty  methods  of  tillage.  This  is  a 
fact  which  the  farmers  of  Illinois  have  not  yet  learned.  The  direction 
of  plowing,  planting,  and  cultivation  is  usually  determined  by~~cbn- 
venience  alone,  regardless  of  consequences.  Plowing  is  more  frequently 
done  up  and  down  the  hill  than  any  other  way,  and  the  making  of  dead 
furrows  in  this  direction  affords  the  best  possible  beginning  for  a 
gully.  The  work  of  one  season's  run-off  may  be  sufficient  to  produce 
a  gully  that  the  next  season's  tillage  operations  will  not  fill,  and  the 
slight  draw  soon  increases  and  becomes  a  source  of  constant  trouble. 

On  land  subject  to  serious  washing,  plowing  should  always  be 
done  along  contour  lines,  or  across  slopes,  the  slopes  being  kept  as 
uniform  as  possible  in  order  to  prevent  any  accumulation  of  water 
in  draws.  When  done  in  this  way,  the  water  in  running  across  the 
furrows  meets  with  more  obstructions  and  greater  resistance  than  in 
running  with  the  furrows,  as  in  up-and-down-hill  plowing,  and  more 
absorption  takes  place. 

While  the  direction  of  plowing  is  important,  the  dep_th  is  of  equal 
importance,  for  a  deep  layer  of  loose  soil  will  absorb  a  heavy  rainfall 
without  run-off.  The  soil  should  be  plowed  to  a  depth  of  six  to  eight 
inches. 

Planting  also  should  be  done  across  the  slope.  The  authors  have 
observed  ditches  six  inches  or  more  in  depth  in  the  track  of  a  planter 
a  week  after  seeding,  where  the  rows  had  been  run  up  and  down  hill. 
All  the  corn  had  been  washed  out  by  the  water  which  had  accumulated 
in  and  followed  the  planter  track.  If  the  corn  rows  had  been  run  on 
the  contour  of  the  slope,  this  could  not  have  taken  place. 

•Cultivating  up  and  down  the  hill  allows  the  accumulation  of  water 
between  rows,  and  this  results  in  the  formation  of  a  large  number  of 
small  gullies,  in  the  making  of  which  much  soil  material  is  removed 
(see  Fig.  15  and  16) .  In  contour  planting,  each  row  retards  the  move- 
ment of  water  down  the  slope,  thus  permitting  greater  absorption. 


534 


BULLETIN  No.  207 


[April, 


FIG.  15. — GULLIES  PRODUCED  IN  A  SINGLE  SEASON  (1916) 
The  corn  was  cultivated  up  and  down  the  slope. 


FIG.  16. — ADVANCED  STAGE  OF  GULLYING  STARTED  IN  THE  SAME  WAY  AS  IN  FIG,  15 


1918]  WASHING  OF  SOILS  AND  METHODS  OF  PREVENTION  535 

Such  crops  as  wheat  and  cowpeas  should  also  be  drilled  along  contour 
lines. 

4.  Tiling. — The  placing  of  lines  of  tile  on  slopes  is  a  very  effect- 
ive way  of  reducing  erosion.    The  soil  is  made  more  porous,  and  conse- 
quently a  large  part  of  the  water  is  removed  thru  the  tile,  instead  of 
collecting  and  running  off  in  draws.     Slopes  frequently  have  places 
where  the  seepage  water  comes  to  the  surface,  producing  cold,  wet 
spots.    This  condition  may  be  entirely  remedied  by  tiling.    The  expense 
involved  is  the  most  serious  objection  to  the  use  of  tile  in  preventing 
erosion. 

5.  Terraces. — In  the  southern  states  it  is  a  common  practice  to 
terrace  cultivated  slopes.    The  type  of  terrace  depends  on  the  steep- 
ness of  the  slope  and  the  character  of  the  surface  soil  and  the  subsoil. 
The  "level  bench,"  "guide  row,"  and  "mangum"  are  all  in  use. 

The  level  bench  is  used  on  the  steeper  slopes.  Contours  are  es- 
tablished at  a  difference  in  elevation  of  three  to  five  feet.  Each  terrace 
is  then  plowed  downward  with  a  hillside  plow.  In  a  few  years  enough 
soil  is  moved  to  make  a  fairly  level  bench.  Each  bench  must  be  cul- 
tivated separately,  and  cuts  or  tracks  across  the  edge  of  the  bench 
must  be  avoided  in  order  to  prevent  destruction  by  erosion. 

The  guide  row  is  developed  by  throwing  several  furrows  together 
on  contour  lines.  Crops  are  seeded  along  or  parallel  to  these  rows. 
In  time,  with  the  use  of  the  hillside  plow,  these  may  easily  be  devel- 
oped into  the  level  bench.  In  both  of  these  types  there  is  a  strip  of 
uncultivated  land  on  the  edge  of  the  terrace.  This  should  have  a 
good  sod  upon  it  to  hold  the  soil.  This  uncultivated  strip  is  undesir- 
able, as  it  is  a  waste  of  land  and  considerable  time  is  required  to  keep 
down  the  weeds,  which  aside  from  their  encroachment  upon  the  crop, 
serve  also  as  a  home  for  mice  and  moles  and  as  a  breeding  place  for 
injurious  insects. 

The  mangum  terrace  (Fig.  17)  differs  from  the  terraces  just 
described  in  that  it  has  some  fall  from  the  back  to  the  front  of  the 
terrace  as  well  as  a  grade  of  about  one  inch  in  ten  feet  from  one  end 
of  the  terrace  to  the  other.  The  width  of  the  terrace  depends  on  the 
general  slope  of  the  area.  In  order  to  build  up  an  embankment,  sev- 
eral furrows  are  thrown  together  along  a  line  of  proper  fall  established 
by  means  of  a  level,  and,  to  increase  its  height,  soil  is  drawn  to  it  from 
the  upper  side,  making  a  low,  broad  dyke.  When  the  field  is  plowed 
again,  the  ridge  may  be  raised  by  back-furrowing  along  the  grade  line. 
This  process  may  be  continued  from  year  to  year  until  the  desired 
height  is  reached.  The  steeper  slopes  require  a  higher  embankment. 
About  six  feet  of  fall  is  allowed  between  embankments,  so  that  the 
terraces  on  very  steep  land  will  be  40  to  80  feet  wide,  and  on  more 
gently  sloping  land  100  to  150  feet  wide.  By  this  method  the  run-off 


536 


BULLETIN  No.  207 


[April, 


FIG.  17. — MANGUM  TERRACE 
(Courtesy,   Bureau  of  Plant  Industry,  U.  S.  D.  A.) 

is  conducted  slowly  around  the  slope  in  a  broad-bottomed  ditch  to  a 
natural  outlet,  without  much  washing.  It  is  essential  that  the  water 
be  given  no  opportunity  to  get  over  the  embankment,  as  it  would  cut 
a  gully  across  it,  drain  the  ditch,  and  ruin  this  and  possibly  several 
embankments  below.  Crops  may  be  planted  in  any  direction,  with 
little  reference  to  the  terraces,  but  it  is  most  desirable  to  have  the  rows 
run  obliquely  across  them,  so  that  there  will  be  a  slight  fall  along  the 
rows  toward  the  ditch.  This  should  aid  the  soil  in  absorbing  more  of 
the  rainfall.  The  mangum  terrace  has  a  distinct  advantage  over  the 
other  types  in  that  there  is  no  waste  land.  This  form  of  terrace  has 
attracted  much  attention,  and  of  the  various  types,  is  the  one  best 
adapted  to  extensive  farming. 

If  cover  crops  and  organic  matter  are  used  to  the  best  advantage, 
and  if  deep  contour  plowing  and  contour  seeding  are  practiced,  there 
will  not  be  much  need  for  any  terracing  in  this  state.  However,  the 
mangum  terrace,  properly  constructed,  may  in  some  places  be  used  to 
advantage. 

FILLING  AND  PREVENTING  GULLIES 

The  owner  of  rolling  or  hilly  land  must  be  constantly  on  the 
lookout  for  new  gullies  and  must  use  every  means  for  preventing  their 
enlargement.  No  attempt  should  be  made  to  crop  the  very  badly 
gullied  areas.  It  would  be  best  to  reforest  these  as  rapidly  as  possible. 


1918}  WASHING  OF  SOILS  AND  METHODS  OF  PREVENTION  537 

This  will  effectually  prevent  further  erosion,  and  after  a  few  years 
will  be  a  source  of  profit  as  well.  Fig.  18  shows  a  grove  of  black  locust 
grown  on  gullied  rolling  hill  land  on  the  farm  of  J.  C.  B.  Heaton, 
in  Johnson  county. 

Care  must  be  taken  to  prevent  shallow  draws  from  becoming  deep, 
untillable  gullies.  A  somewhat  common  method  is  to  scatter  straw 
in  them,  or  to  build  dams  of  straw  across  them  at  frequent  intervals. 
This  is  often  done  in  wheat  fields  after  seeding  in  the  fall.  Such  a 
method  may  serve  to  check  the  velocity  of  the  water  and  to  catch  the 
sediment,  but  frequently  the  run-off  is  so  great  that  the  water1  washes 
around  the  ends  of  the  dams  or  carries  the  straw  down  the  draw  and 
deposits  it  at  the  base.  These  dams  are  sometimes  held  in  place  by 
rows  of  stakes  driven  across  the  draw. 


FIG.  18. — BLACK  LOCUSTS  GROWING  ON  BADLY  ERODED  LAND 
Farm  of  J.  C.  B.  Heaton,  Johnson  county. 

A  better  plan,  used  a  great  deal  in  some  parts  of  the  state,  is  to 
keep  these  draws  well  sodded,  at  least  until  they  are  so  well  filled  that 
there  is  little  danger  of  gullies  forming  (Fig.  19).  The  sod  binds  the 
soil  particles  together,  while  the  top  growth  checks  the  velocity  of  the 
water,  causing  the  suspended  sediment  to  be  deposited.  In  time  the 
draw  becomes  filled  so  that  it  may  be  cropped,  but  it  should  be  seeded 
down  again  if  there  is  danger  of  a  gully  forming.  Almost  any  grass 


538 


BULLETIN  No.  207 


[April, 


FIG.  19. — SODDED  DRAW  IN  MERCER  COUNTY 


FIG.  20. — DAMS  OP  STRAW  HELD  BY  WOVEN  WIRE  FENCING,  MASON  COUNTY 

that  forms  a  tough  sod  will  answer  the  purpose,  timothy,  red-top,  and 
blue  grass  being  quite  satisfactory.  This  method  is  practiced  very  suc- 
cessfully in  some  parts  of  the  state.1  The  grass  may  be  mowed  for  hay. 

'Some  owners  in  renting  their  land  insert  a  clause  in  the  lease  forbidding  the 
plowing  up  of  these  draws. 


1918] 


WASHING  OF  SOILS  AND  METHODS  OF  PREVENTION 


Where  the  gullies  are  small,  the  matter  of  filling  them  is  a  simple 
one,  altho  care  and  perseverance  are  required  to  keep  them  filled.  If 
it  is  desirable  to  crop  the  field  soon,  and  the  gullies<  are  not  too  deep, 
they  may  be  filled  with  the  plow  and  scraper  in  a  comparatively  short 
time  and  at  little  expense.  A  depression,  or  draw,  must  not  be  left 
where  the  gully  formerly  was,  or  it  will  be  a  constant  source  of  trouble. 

Dams  of  earth,  stone,  concrete,  or  straw  held  by  woven  wire  (Fig. 
20 )  are  sometimes  constructed  across  a  gully  in  order  to  catch  the  sedi- 
ment and  thus  fill  the  gully  and  prevent  its  later  formation  in  the  same 
draw.  In  many  cases  this  method  has  been  very  satisfactory.  It  may 
be  used  for  draws  as  well  as  for  gullies. 


FIG.  21. — A  GULLY  IN  CENTRAL  ILLINOIS 

This  gully  started  less  than  forty  years  ago,  and  is  now  from  100  ta  150  feet 
wide  and  from  25  to  65  feet  deep. 

The  construction  of  these  dams  should  vary  with  the  size  of  the 
gully  and  the  amount  of  water  flowing  thru  it.  If  the  gully  is  small, 
an  earth  dam  constructed  as  shown  in  Fig.  22,  may  be  all  that  is 
necessary  to  prevent  its  enlargement  (see  Fig.  23).  If  the  gully  is 
large,  and  the  volume  of  water  considerable,  a  concrete  dam  should 
be  used  which,  in  addition  to  the  tile,  has  a  spillway  over  which  the 
excess  water  may  flow.  An  apron  of  concrete  should  be  placed  under 
the  spillway  to  prevent  the  undermining  of  the  dam. 

Fig.  24  shows  a  detailed  plan  that  may  be  used  as  a  guide  in  the 
construction  of  a  concrete  dam.  The  concrete  should  be  well  rein- 
forced and  anchored  on  each  side.  The  tile  may  be  placed  so  as  to  run 
either  under  the  dam  or  thru  it.  Care  must  be  taken  to  build  the  dam 


540 


BULLETIN  No.  207 


[April, 


with  sufficient  strength  to  resist  the  pressure  of  the  water.  The  con- 
crete should  extend  at  least  two  feet  below  the  bed  of  the  stream,  or 
below  the  frost  line.  Figs.  25  and  26  show  concrete  dams  in  place. 


FIG.  22. — DAM  OF  EARTH 

The  tile,  both  vertical  and  horizontal,  must  be  large  enough  to  allow  the  water 
to  flow  away  without  any  of  it  going  over  the  dam,  as  that  will  ruin  it. 

The  gully  produced  by  a  waterfall  is  one  of  the  hardest  to  fill, 
since  the  fall  of  the  water  gives  it  great  eroding  power,  making  it 
very  difficult  to  stop  its  undermining  action.  As  such  gullies  generally 
occur  where  the  field  is  in  grass,  there  is  a  comparatively  small  amount 
of  sediment  carried,  and  consequently  the  filling  goes  on  but  slowly. 
The  problem  is  to  stop  the  recession.  Straw  and  brush  should  be  placed 
under  the  fall  and  weighted  down  with  stones  or  sod,  or  held  in  place 
with  stakes  to  prevent  their  being  washed  away.  Dams  of  straw  or 
brush  should  be  placed  at  intervals  below  the  fall,  and  even  a  solid  dam 
of  concrete  where  the  gully  passes  into  another  field  may  be  of  much 
service  in  completely  filling  it  in  time. 


FIG.  23. — DITCH  IN  CHAMPAIGN  COUNTY  FILLED  BY  MEANS  OF  EARTH  DAM 

The  gully  was  six  feet  deep  and  sufficiently  wide  at  the  bottom  for  a  team 
and  wagon  to  stand  crosswise.     It  was  filled  in  less  than  ten  years. 


1918] 


WASHING  OF  SOILS  AND  METHODS  OF  PREVENTION 


541 


2.0'. 


TV 


(3) 


FIG.  24. — DETAILED  PLAN  FOR  A  CONCRETE  DAM 


(1)  View  from  above;  (2)  Looking  upstream;  (3)  Section.  C — Upstream 
apron  for  preventing  under  wash  ing.  D — Spillway  apron  of  concrete.  E-E — Con- 
crete abutments  for  bracing  the  main  dam.  F — Steel  reenforcing  rods,  horizontal 
and  vertical.  G — Permanent  tile  for  draining  ditch  when  filled  with  sediment  (the 
size  of  the  tile  will  vary  with  the  needs,  and  may  run  under  the  spillway  if  the 
ditch  is  not  deep).  II — An  opening  may  be  left  in  the  dam  to  take  care  of  the 
water  under  ordinary  conditions  and  reduce  the  size  of  the  pond  above  the  dam; 
this  opening  should  be  closed  when  the  ditch  is  filled  with  sediment  to  that  level. 


S42 


BULLETIN  No.  207 


[April, 


rt  5 

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'1918]  WASHING  OF  SOILS  AND  METHODS  OF  PREVENTION  ^  '       543 

RECLAMATION  EXPERIMENTS 
JOHNSON  COUNTY  EXPERIMENT  FIELD  AT  VIENNA,  ILLINOIS 

In  the  spring  of  1906  the  Agricultural  Experiment  Station  of 
the  University  of  Illinois  purchased  sixteen  acres  of  land  in  Johnson 
county  near  Vienna.  The  whole  area,  with  the  exception  of  about 
three  acres,  had  been  abandoned  because  so  much  of  the  surface  soil 
had  been  washed  away,  and  there  were  so  many  gullies  that  further 
cultivation  was  unprofitable  (Fig.  27).  The  land  was  bought  for  the 
purpose  of  reclaiming  it  and  studying  different  methods  of  reducing 
erosion. 


HIM 


I  I 


w 


FIG.  27. — VIEW  OF  LAND  IMMEDIATELY  ADJOINING  THE  VIENNA  EXPERIMENT  FIELD 
When  the  land  was  purchased,  gullying  had  not  gone  very  far.  (See  Fig.  28.) 

Part  of  the  land  was  occupied  by  scrub  trees,  persimmon,  elm,  and 
sassafras,  and  by  blackberry  and  other  brush.  This  was  removed  and 
used  in  making  brash  dams  in  the  ditch  running  north  and  south  across 
the  middle  of  the  field.  Some  of  the  gullies  were  from  four  to  five  feet 
deep,  so  that  the  first  step  in  reclaiming  the  land  was  to  fill  them  and 
make  the  slopes  more  uniform.  This  was  accomplished  with  plows 
and  scrapers. 

The  soil  was  extremely  low  in  organic  matter,  the  subsoil  being 
exposed  on  about  one-fourth  of  the  field.  These  conditions  were 
responsible  for  a  large  part  of  the  run-off,  the  low  productiveness  of 
the  soil,  and  the  injury  to  crops  by  drouth.  In  two  places,  about  a 
square  rod  of  the  underlying  rock  was  exposed. 


544 


BULLETIN  No.  207 


[April, 


The  field  was  divided  into  five  series,  A,  B,  C,  D,  and  E,  as  shown 
in  Fig.  29.  The  division,  it  will  be  noticed  by  the  contour  lines,  was 
more  or  less  natural  to  the  lay  of  the  land.  Series  A,  B,  C,  and  D, 
together  with  divisions  and  borders,  occupy  about  thirteen  acres, 
and  Series  E  about  three  acres.  A,  B,  and  C  were  divided  into  four 
plots  each ;  D,  into  three  plots.  For  each  series  a  somewhat  different 
system  of  reclamation  was  planned  in  order  not  only  to  study  the  prob- 
lems of  reducing  erosion,  but  also  to  determine  which  system  of  reclam- 
ation was  best  under  these  conditions,  as  indicated  by  the  crop  yields. 

Series  A  includes  the  steepest  part  of  the  area  and  contained  many 
gullies.  These  were  filled  and  the  area  was  terraced  at  vertical  inter- 
vals of  five  feet.  Near  the  edge  of  each  terrace,  which  had  a  slight 
slope,  a  small  ditch  was  placed,  so  that  the  water  could  be  carried  to 
a  natural  outlet  at  the  side  of  the  field  without  doing  much  washing. 
Each  terrace  was  cropped  as  a  separate  area. 

In  two  places  in  Series  B  were  several  small  gullies,  none  of  which 
was  more  than  eighteen  inches  deep.  On  this  series  the  embankment 
method  was  used,  except  at  the  steepest  part,  where  two  hillside  ditches 
were  made  for  carrying  away  the  run-off. 

Series  C  was  washed  badly  but  contained  only  small  gullies.  On 
this  series  an  attempt  was  made  to  prevent,  washing  by  incorporating 
organic  matter  in  practicable  amounts.  In  the  spring  of  each  year, 
with  the  exception  of  two  years,  manure  at  the  rate  of  about  eight  loads 
per  acre  was  turned  under  for  corn. 

Series  D  lies  just  across  the  hollow  from  Series  C,  and  was  washed 
to  about  the  same  extent.  As  a  check  against  the  various  methods 
for  reducing  erosion,  Series  D  was  farmed  in  the  most  convenient 
way,  without  any  special  effort  being  made  to  prevent  washing. 


-*i«;c  * 

^.•TTV***;^ 

^"    -  —  - 


FIG.  28. — SAME  AS  FIG.  27,  BUT  TEN  YEARS  LATER 


1918} 


WASHING  OF  SOILS  AND  METHODS  OP  PREVENTION 


545 


These  series  (A,  B,  C,  and  D)  were  not  entirely  uniform.  As 
already  stated,  some  parts  were  washed  worse  than  others,  and  sections 
of  the  lower  part  of  the  field  had  been  affected  by  soil  material  brought 
from  the  higher  land.  When  the  field  was  secured,  this  higher  land 
had  a  very  low  productive  capacity,  as  shown  by  the  yield  of  9.7 
bushels  of  corn  on  Series  D,  and  11.1  bushels  on  Series  C,  in  1906, 
the  first  year.  Many  spots  would  grow  little  or  nothing. 

Series  E  was  badly  eroded  and  gullied  and  was  not  cropped.  An 
attempt  was  made  to  fill  the  gullies  by  putting  brush  into  them  and 
seeding  to  grass,  but  this  was  not  wholly  successful.  The  area  above 
the  gullies  was  soon  covered  with  vegetation,  so  that  there  was  little 
soil  material  washed  into  the  ditches  to  aid  in  filling  them.  However, 
the  grass  and  brush  prevented  the  gullies  from  becoming  larger. 

Limestone  was  applied  to  the  entire  field  at  the  rate  of  two  tons 
per  acre.  No  other  mineral  plant  food  was  applied.  Corn,  cowpeas, 
wheat,  and  clover  were  grown  every  year  in  the  order  named,  as  a 


FIG.  29. — MAP  OF  UNIVERSITY  OF  ILLINOIS  SOIL  EXPERIMENT  FIELD  AT  VIENNA 

Showing  location  of  the  series  and  the  approximate  contour  lines  (5-foot  in- 
tervals).    The  sharp  bends  in  contour  lines  show  where  largo  gullies  were  located. 


546 


BULLETIN  No.  207 


[April, 


four-year  rotation,  together  with  additional  cover  crops  when  nec- 
essary. The  corn  stalks,  the  second  growth  of  clover,  and  the  cowpeas 
were  turned  back  into  the  soil.  When  clover  failed,  soybeans  were  sub- 
stituted, but  these  did  not  make  a  large  growth  (seldom  more  than 
an  ordinary  second  growth  of  clover) ,  and  were  turned  under. 

Tables  9,  10,  and  11  give  the  yields  of  the  crops  by  plots  on  each 
series. 

TABLE  9. — YIELDS  OF  CORN  IN  SOIL  EXPERIMENTS,  VIENNA  FIELD:  1906-1915 

(Bushels  per  acre) 


Year 

Plot 

A 

B 

C 

D 

1906 

i 

42.1 

18.6 

11.1 

9.7 

1907 

4 

17.8 

24.8, 

31.0 

No  plot 

1908 

3 

25.0 

44.0 

31.5 

31.1 

1909 

2 

30.8 

41.5 

41.2 

13.5 

1910 

1 

52.5 

36.0 

27.7 

8.0 

1911 

4 

30.0 

31.9 

36.5 

No  plot 

1912 

3 

13.7 

37.5 

10.8 

24.4 

1913 

9 

24.6 

36.4 

41.8 

8.2 

1914 

1 

30.8 

13.5 

22.6 

3.7 

1915 

4 

24.5 

14.8 

32.1 

No  plot 

Average  . 

29.2 

29.9 

28.6 

14.1 

TABLE  10. — YIELDS  OF  WHEAT  IN  SOIL  EXPERIMENTS,  VIENNA  FIELD:  1906-1915 

(Bushels  per  acre) 


Year 

Plot 

A 

B 

C 

D 

19061 

1907 

2 

8.9 

10.6 

9.4 

5.6 

1908 

1 

8.9 

6.2 

8.5 

1.5 

1909 

4 

7.3 

7.0 

12.0 

No  plot 

1910 

3 

11.5 

18.8 

16.7 

7.8 

1911   . 

2 

13.1 

19.6 

20.1 

3.7 

1912 

1 

3.0 

2.8 

0 

0 

1913 

4 

6.9 

10.0 

12.5 

No  plot 

1914 

3 

9.3 

14.7 

11.1 

8.4 

1915 

2 

8.5 

15.3 

14.8 

5.1 

Average. 

8.0 

11.6 

11.7 

4.6 

'Oats  were  sown  instead  of  wheat,  but  they  did  not  grow  high  enough  to  be 
harvested. 

TABLE  11. — YIELDS  OF  CLOVER  IN  SOIL  EXPERIMENTS,  VIENNA  FIELD:  1907-1915 

(Tons  per  acre) 


Year 

Plot 

A 

B 

C 

D 

1907 
1908 
1909 
1910 
1911 
1912 
1913 
1914 
1915 

3 
2 
1 
4 
3 
2 
1 
4 
3 

.75 
.20  . 

1.11 
1.04 

.29 
.30 

.40 
.10 

Clover  turned  under 

.46    - 

1.08 

1.20 

No  plot 

Failure 

Soybeans  turned  under 

1.09 

.78 

1.81 

.14 

Soybeans  turned  under 

Sweet  clover  turned  under 

Soybeans  turned  under 

Average  

.62 

1.00 

.90 

.21 

1918] 


WASHING  OF  SOILS  AND  METHODS  OF  PREVENTION 


547 


It  is  difficult  to  compare  the  results  obtained  from  the  various 
methods  of  treatment  on  the  different  series  because  of  the  variation 
in  the  soil,  but  it  can  be  said  that  any  system  that  conserves  the  soil 
will  aid  in  maintaining  the  crop  yields.  Table  12  gives  by  periods 
the  crop  yields  obtained  under  the  different  methods  of  management. 

TABLE  12. — ANNUAL  CROP  YIELDS  OBTAINED  UNDER  DIFFERENT  METHODS  OF 
MANAGEMENT  TO 'REDUCE  EROSION:  VIENNA  FIELD 


Years 

Terrace 
(A) 

Embankments  and 
hillside  ditches 
(B) 

Organic  matter,  deep 
contour  plowing, 
and  contour 
planting  (C) 

Check 
(D) 

Corn  (Bushels  per  acre) 


1906-08 
1909-11 
1912-15 

28.3 
37.7 
23.4 

29.1 
36.5 
25.6 

24.5 
35.1 
26.8 

20.41 
10.71 

12.12 

Average  

29.2 

29.9 

28.6 

14.1 

Wheat  (Bushels  per  acre) 


1907-09 
1910-12 
1913-15 

Average  

8.3 
9.2 
7.6 

7.9 
13.7 
13.3 

10.0 
12.3 
12.8 

3.51 
5.71 
6.3 

8.6 

11.6 

11.7 

5.3 

Clover  (Tons  per  acre) 

1907-8-10-13 

.62 

1.00 

.90 

.21 

aTwo-year  average.    2Three-year  average. 

The  average  yield  of  corn  for  1912  to  1915  was  less  than  for  1906 
to  1908  in  every  case  except  where  the  organic  matter  was  increased. 
This  was  due  in  part  to  the  three  dry  seasons  during  the  1912  to  1915 
period.  Series  -C  and  D  were  on  either  side  of  a  draw  extending  north 
and  south,  C  facing  west  and  D  east.  Series  C  received  manure  in 
addition  to  the  cowpeas  and  residues  turned  under,  and  every  effort 
was  made  to  prevent  washing,  tho  this  was  not  successful  in  all  cases. 
Series  D,  of  which  no  particular  care  was  taken,  is  now  almost  worth- 
less because  of  gullying  (Fig.  30).  Table  13  gives  the  average  yields 
for  the  four  series,  based  on  all  comparable  yields. 

TABLE  13. — AVERAGE  OF  COMPARABLE  YIELDS,  VIENNA  FIELD:  1906-1915 


Crops 

Years 

Series 

A 

B 

C 

D 

Corn  (bu.  per  acre)  

7 
7 
3 

31.4 
9.0 
0.68 

32.4 
12.7 
0.97 

27.9 
11.7 
0.80 

14.1 
4.6 
0.21 

Wheat  (bu.  per  acre)  

Clover  (tons  per  acre)  

The  average  yield  of  corn  for  the  protected  series  (A,  B,  and  C) 
was  30.6  bushels  per  acre,  as  against  14.1  bushels  for  series  D ;  wheat 
yielded  11.1  bushels  in  comparison  with  4.6  bushels,  and  clover  0.82 
ton  in  comparison  with  0.21  ton. 


548 


BULLETIN  No.  207 


[April, 


FIG.  30. — VIEW  OP  PART  OF  SEKIES  D,  1916,  VIENNA  EXPERIMENT  FIELD 
Note  badly  eroded  condition. 

The  best  biennial  legume  for  soil  improvement  on  eroded  land 
is  sweet  clover,  because  as  already  stated,  it  catches  readily  and  makes 
a  large  growth  of  both  top  and  root.  The  second  season's  growth 
begins  sufficiently  early  so  that  if  desired  a  considerable  amount  may 
be  plowed  under  for  corn  the  same  season  (see  Fig.  31). 

The  comparison  between  Series  C  and  Series  D  may  be  somewhat 
in  favor  of  C  since  C  received  some  manure.  Series  A,  however,  was 
washed  as  badly  as  D  in  all  except  the  northeast  and  southeast  parts, 
and  aside  from  terracing  received  the  same  treatment  as  D.  The  dif- 
ference in  yields  here  is  almost  as  striking  as  between  C  and  D.  As 
an  average  of  the  comparable  yields,  A  produced  31.4  bushels  of  corn 
per  acre  and  D,  14.1  bushels ;  A  produced  9.0  bushels  of  wheat  and  D, 
4.6  bushels ;  A  produced  .68  ton  of  clover  and  D,  .21  ton.  Reclaiming 
and  reducing  erosion  resulted  in  an  increase  of  17.3  bushels  of  corn 
per  acre,  4.4  bushels  of  wheat,  and  .47  ton  of  clover  hay. 

Figuring  corn  at  60  cents  and  wheat  at  80  cents  per  bushel  and 
clover  hay  at  $7  per  ton,  the  value  of  the  increase  due  to  reclamation 
and  control  of  erosion  for  one  four-year  rotation  is  $17.19.  These 
three  crops  represent  the  total  yield  per  acre,  as  the  cowpeas  were 
turned  under.  The  average  annual  gain  per  acre  is  $4.30;  which 
would  mean  $172  a  year  from  forty  acres,  and  $1,720  in  ten  years 
from  forty  acres. 

The  expense  of  reclaiming  the  land,  which  for  series  A  and  B 
consisted  in  filling  gullies  and  building  terraces  and  embankments, 


1918] 


WASHING  OF  SOILS  AND  METHODS  OF  PKEVENTION 


549 


was  approximately  $18  on  5.8  acres.  About  two-thirds  of  this  amount 
was  spent  on  Series  A,  which  had  been  completely  abandoned  when  the 
tract  was  purchased  and  was  badly  gullied  and  more  difficult  to  ter- 
race. Series  C  and  D  required  but  little  work,  since  they  contained 
only  a  few  small  gullies  and  no  terracing  was  done. 

The  value  of  the  crops  removed  from  Series  A  during  the  first 
rotation  was  $66.08,  or  at  the  rate  of  $26.43  per  acre  for  four  years, 
or  $6.61  per  acre  per  annum.  The  crops  of  cowpeas  are  not  included 
in  the  above.  If  $6  per  ton  is  allowed  for  the  cowpea  hay,  the  value 
of  the  crops  will  be  increased  about  $4.50  per  acre,  making  approxi- 
mately $11.11  per  acre  on  this  formerly  abandoned  land.  The  approx- 
imate costj  of  maintaining  the  terraces  on  Series  A  was  not  over  fifty 
cents  per  acre  per  annum,  and  much  less  on  Series  B. 

This  increase  in  returns  pays  for  all  labor  of  filling  gullies  and 
building  terraces  and  maintaining  them,  and  leaves  a  fair  profit  on 
each  field  where  washing  is  largely  prevented  and  the  soil  conserved. 
Series  A  is  in  a  condition  to  be  cultivated  for  years  to  come  if  properly 
cared  for,  while  Series  D  cannot  be  cropped  profitably  in  its  present 
condition. 


FIG.  31. — SWEET  CLOVER  ON  VIENNA  EXPERIMENT  FIELD 
About  30  inches  high,  May  31,  1914. 


550 


BULLETIN  No.  207 


[April,  1918 


Increasing  and  maintaining  the  organic  matter,  using  cover  crops, 
keeping  the  land  in  pasture  and  meadow  as  much  as  possible,  and  prac- 
ticing deep  contour  plowing  and  planting  are  the  most  practical  means 
for  reducing  soil  washing  in  Illinois.  If  these  methods  are  practiced, 
much  of  the  badly  eroded  land  can  be  cultivated  with  profit. 


FIG.  32. — CORN  ON  VIENNA  EXPERIMENT  FIELD 

Upper  Section — Series  D,  1914;  yield  3.7  bushels. 
Lower  Section — Series  C,  1914;  yield  22.6  bushels. 


AUTHOR  INDEX 


557 


AUTHOR  INDEX 


PAGE 

Allyn,  O.  M.,  ami  Burlison,  W.  L. 
Soybeans  and  Cowpeas  in 
Illinois 1-20 

Allyn,  O.  M.,  and  Burlison,  W.  L. 
Yields  of  Winter  Grains  in 
Illinois 95-110 

Burlison,  W.  L.,  and  Allyn,  O.  M. 
Soybeans  and  Cowpeas  in 
Illinois 1-20 

Burlison,  W.  L.,  and  Allyn,  O.  M. 
Yields  of  Winter  Grains  in 
Illinois 95-110 

Bin-rill,  Thomas  J.,  and  Hansen, 
Eoy.  Is  Symbiosis  Possible 
between  Legume  Bacteria 
and  Non-Legume  Plants?.  111-181 

Carmichael,  W.  J.,  Grindley,  H. 
S.,  and  Newlin,  C.  I.  Diges- 
tion Experiments  with  Pigs 
with  Special  Reference  to 
the  Influence  of  One  Feed 
upon  Another,  and  to  the  In- 
dividuality of  Pigs 53-94 

Chambers,  W.  H.,  Prucha,  M.  J., 
and  Weeter,  H.  M.  Germ 
Content  of  Milk  as  Influ- 
enced by  the  Utensils.  .  .  .215-257 

Crandall,  Charles  S.  Seed  Pro- 
duction of  Apples 184-213 

Grindley,  H.  S.,  Carmichael,  W. 
J.,  and  Newlin,  C.  I.  Diges- 
tion Experiments  wifh  Pigs 
with  Special  Reference  to  the 
Influence  of  One  Feed  upon 
Another,  and  to  the  Individ- 
uality of  Pigs 53-94 

Gunderson,  A.  J.,  Pickett,  B.  S., 
Watkins,  O.  S.,  and  Ruth, 
W.  A.  Field  Experiments  in 
Spraying  Apple  Orchards  in 
1913  and  1914 427-509 

(Justafson,  A.  F.,  and  Mosier,  J. 
G.  Washing  of  Soils  and 
Methods  of  Prevention.  .511-550 

Hanson,  Roy,  and  Burrill,  Thomas 
J.  Is  Symbiosis  Possible  be- 


PAGE 

tween  Legume  Bacteria  and 
Non-Legume  Plants!   ...111-181 

Mother,   Edna.      The  Grasses   of 

Illinois  , 259-425 

Mosier,  J.  G.,  and  Gustafson,  A. 
F.  Washing  of  Soils  and 
Methods  of  Prevention.  .  .511-550 

Newlin,  ,C.  I.,  Grindley,  H.  S.,  and 
Carmichael,  W.  J.  Diges- 
tion Experiments  with  .Pigs 
with  Special  Reference  to  the 
Influence  of  One  Feed  upon 
Another,  and  to  the  Individ- 
uality of  Pigs 53-94 

Pickett,  B.  S.,  Watkins,  O.  S., 
Ruth,  W.  A.,  and  Gunderson, 
A.  J.  Field  Experiments  in 
Spraying  Apple  Orchards  in 
1913  and  1914 427-509 

Prucha,  M.  J.,  and  Weeter,  H.  M. 
Germ  Content  of  Milk  as 
Influenced  by  the  Factors  at 
the  Barn  21-52 

Prucha,  M.  J.,  Weeter,  H.  M.,  and 
Chambers,  W.  H.  Germ  Con- 
tent of-  Milk  as  Influenced 
by  the  Utensils ....  .  .215-257 

Ruth,  W.  A.,  Pickett,  B.  S.,  Wat- 
kins,  O.  S.,  and  Gunderson, 
A.  J.  Field  Experiments  in 
Spraying  Apple  Orchards  in 
1913  and  1914 427-509 

Watkins,  O.  S.,  Pickett,  B.  S., 
Ruth,  W.  A.,  and  Gunderson, 
A.  J.  Field  Experiments  in 
Spraying^  Apple  Orchards  in 
1913  and  1914 427-509 

Weeter,  H.  M.,  and  Prucha,  M.  J. 
Germ  Content  of  Milk  as  In- 
fluenced by  the  Factors  at 
the  Barn  21-52 

Weeter,  II.  M.,  Prucha,  M.  J.,  and 
Chambers,  W.  H.  Germ  Con- 
tent of  Milk  as  Influenced 
by  the  Utensils 215-257 


558 


VOLUME  14 


INDEX 


(The  headings  in  capitals  are  subjects  of  entire  'bulletins) 


PAGE 

Acacia 119,  135,  139,  140 

armata 129,  131,  136 

floribunda. .  .123,  129,  131,  134,  136 

from  California 129,  131,  136 

linifolia 129,  131,  136 

longi folia    129,   131,  136 

melanoxylon   131,  136,  154 

semperflora 129,  131,  136 

Alfalfa,  see  Medicago 

Alnus  145,  149-50,  160 

glutmosa 150 

Amorpha  canescens.131,  134,  135,  137 

Amphicarpa 119,  135,  139 

monoica 123,  131,  133, 

134,  135,  137,  149 

Anthyllis 135 

vulneraria 133 

Apple  blotch 452,  454-57,493,  499 

Sprays  for 506-07 

Apple  flea- weevil   452,  453 

Apple-leaf  roller    452,  453 

APPLE     OECHARDS,     FIELD 
EXPERIMENTS  IN 
SPRAYING,   IN 

1913  AND   1914 427-509 

Index  to  bulletin 509 

Apple  scab,  on  foliage ..  452,  453,  472 

on  fruit 454-57,  460-71,  488, 

490-93,  497-99 
Sprays  for   505—07 

APPLES,  SEED  PRODUCTION 

IN 183-213 

Number  of  seeds 185 

Opinions  regarding 185-87 

Orchard  varieties 189-200 

Records 187-89 

Under   controlled  pollination .  . 

211-13 

See  also  Crab  apples 

Arachis 119,  135,  139 

hypogoea   123,  131,  134, 

135,  136,  149,  153 

Archips  rosaceana 452 

Bacteroids 121-22 

Banding  trees  for  control  of  cod- 
ling moth 447,  448,  504 

Ba-ptisia 119,  139 

tinctoria 123,  131,  134,  135,  136 

Barley,  Ground,  for  pigs.  .75,  77,  79- 

80,  81 
Winter,  Tests  with 99,  106-08 

Barns,  see  Dairy  barns 

Bean,  see  Phaseolus 

Bean,   wild,  see  Strophostyles 


PAGE 


Bitter  rot  of  apples,  Sprays  for 

507,  508 
Blotch,  Apple,  sec  Apple  blotch 

Blue  grass  as  cover  crop 527-28 

Bordeaux  injury,  see  Russet, 
Bordeaux 

Bud  moth,  Spray  for 505 

Burn,  Lime  sulfur. 429,  445,  448,  474- 
78,  480-86,  489,  494-98,  501,  504 

Canterworm,  Spray  for 505 

Cassia, 119,  135,  139,  140 

chamaccrista. . .  .123,  127,  131,  134, 
135,  136,  137   (note) 

medsgeri 136  (note) 

nictitans 136  (note) 

Ceanothus 115,  145,  152,  160 

americanus 145-48 

Clover 

as  cover  crop 527-28 

Nitrogen  content  of 532 

See  also   Trifolium 
Clover,  Sweet 

as  cover  crop 527-28 

for  improvement  of  eroded  land 

532.  548 

Nitrogen  content  of 532 

See  also  Melilotus 

Codling  moth.  .429,  432-40,  441,  44o- 

48,   452,   454-57,   460,   461,   463- 

71,   472-89,  490-93,  495-97,  499, 

502-04 

Sprays  for 477-79,  506-08 

Connecticut   river   basin,   Run-off 

from 518 

Corn 

Ground,  for  pigs 62-63,  68,  69, 

77,  79-80 

Inoculation 151 

Nitrogen  requirements    S32-33 

Corn  stalks,  Nitrogen  content  of.  532 
Cover  corps  to  reduce  erosion . .  52(5-28 
Cowpea 

as  cover  crop 527 

grown  in  Illinois 1-20 

Nitrogen  content  of 532 

Sec  also  Viana 
Crap  apples,  Seed  production   iu 

200-11,  212,  213 

Crab  grass  as  cover  crop 527 

Cracking  of  apples 437,  438 

Cross-inoculation 125-40,  160 

Cowpea  X  several  generic 

groups 131-33 


INDEX 


559 


PAGE 

Carman's  method 125,  127,  133, 

134,  153 
Grouping    by    scrological    tests 

and   cultural    differences.  .137-40 
Lens  X   several   generic 

groups 133 

Vigna  X  Acacia 129-31 

Vigna  X   Cassia 127-29 

Ctirculio 460-71,  474,  476,  478-88, 

490,  492,  493-97,  499 

Sprays   for    506-07 

Cutler,   111.,  Tests  of  winter  rye, 

barley,  emmer,  and  oats..  106-08 

Cycas 115,  145,  150,  152,  160 

rcvoluta 148-49 

Dairy  barns  used  in  experiments 

on  germ  content  of  milk .  .  .  26-29 

Dams,  Construction  of 539-42 

De  Kalb,  111.,  Tests  of  winter  rye 

and  barley  99,  101 

De  Kalb  experiment  field 97 

Desmodium  119,  135,  139 

canescens 123,  131,  134,  135, 

136,  149,  154 

illinoense 134,  135,  136 

Digestion  experiments,  see  Pigs 

Elaeagnus 115,  145,  149-50, 

152,  160 
Embarrass    river    basin,    run-off 

from 518 

Erosion 511-50 

Cause 519-20 

Changes  in  physical  character  of 

soil  due  to 525 

Cover  crops  to  reduce 526-28 

Effects 522-25 

Filling  and  preventing  gullics.536-42 
Increasing  organic-matter   con- 
tent to  reduce 528-33 

Kinds 519-21 

Methods  of  reducing 526-36 

Reclamation      experiments      at 

Vienna 543-50 

Terraces  to  reduce 535-36 

Tiling  to  reduce 535 

Tillage  to   reduce 533-35 

Fail-field,    111.,    Variety    tests    of 

winter  wheat 104-06,  107 

False  indigo,  see  Baptisia 
Flora,  111.,  Spraying  experiments 

449-57 

Fail-field  experiment  field 97 

Fenugreek,  see   Trigonella 

FranTcia  bruncliorslii 145 

ccanothi 145,  148 

subtilis 145 

Fr»g*-eye  fungus,  see  Leaf  spot 
Carman's  method  of  cross-inocu- 
lation   125,  127,  133, 

134,  153 


PAGE 

Genista 119,  139 

tinctorM 123,  131,  134, 

135,  136,  154 
Germ  content  of  milk,  studies  of 

21-52,  215-57 

Glycine.  . .'. 119,  127,  135,  139 

hispida 123,  134,  135,  137, 

149,   153,   154 
GRAINS,  YIELD  OF  WINTER, 

IN  ILLINOIS 95-110 

GRASSES  OF  ILLINOIS,  THE 

259-425 

Bibliography 419 

Descriptions     and    distribution 

275-419 

Index  to  common  names ....  423-25 
Index  to  scientific  names.  .  .420-23 

Key  to  genera  of 269-74 

Griggsville,  111.,  Spraying  experi- 
ments   458-89 

Gullying,  see  Erosion 

Hog  peanut,  see  Amphwarpa 

Illinois,  Area  513 

Rainfall 517 

Illinois  river  basin,  Run-off  from 

518,  519 

Japan  clover,  see  Lcspedeza 
Kaskaskia    river    basin,    Run-off 

from 518 

Kidney  vetch,  see  Anthyllis 

Lathyrus 119,  127,  139 

latifolius 133,  136 

odoratus 123,   136,  154 

Lead  plant,  see  Amorpha 
canescens 

Leaf  burning 434,  445,  484 

of  tip  and  edge 465,  468,  470, 

474,  475,  479,  481,  486 

Leaf  spot 452,  453,  460, 

463,  467,  468,  470,  494 

Spray  for   506 

Legume     bacteria,     see    Pseudo- 

monas  radicicola 

LEGUME  BACTERIA  AND 
NON-LEGUMES,  POSSI- 
BLE SYMBIOSIS  BE- 
TWEEN   111-81 

Legumes 

as  cover  crop 526-28 

to  improve  eroded  land 531-32 

Lcguminosae,  Histology  of  nod- 
ules of 141 

Lens  119,  135,  139 

esculcnta 135,  136 

Lentil,  .s'ec  Lens 

Lcspedesa   119,  135,  139 

striata 123,  131,  134,  135,  136 

virf/inica 134,  135,  136 

Lupine,  see  Liipinvs 


560 


VOLUME  14 


PAGE 

Lupinus   119,  135 

perennis 134,  135,  137,  149 

Mains,  Experiments  in  seed  pro- 
duction  187-189,  200-213 

Mangum  terrace   535—36 

Medicago   119,  127,  135,  139 

falcata 136 

hispida 136 

lupulina   134,  136 

sativa 123,  133,  134,  136,  148 

Mdilotus 119,   127,   135,  139 

alba 123,  133,  134,  136, 

148,  152,  153,  154 

indica    134,  136 

oificinalis    134,  136 

Middlings   61-63,  67,  69 

Milk 

as  source  of  bacteria 231-33 

Experiments  to  determine  germ 

content  . 21-52,  215-57 

at    New    York    Agricultural 
Experiment  Station .  25-26,  217 

Barns  used   26-29 

Conclusions 51,  257 

Methods  of  study.  .30-32,  219-20 

Kesults 32,  46-48 

Germ  content 

Bacteria     added     by     barn 

factors 48-50 

of  all  milk  at  different  milk- 
ings  43-46 

of  individual  samples 33-41 

of  milk  of  different  animals.41-42 

Souring  of   217 

Utensils 

Bacteria  in 219-20,  221-31 

Bottle    filler,     influence     on 

germ  content   248-50 

Bottles,  bacteria  in 241-44 

Influence  at  barn 

245-47,    250-54,    256 

Influence  on  germ  content. 221-44 

Previous  studies 218-19 

Sterilization 30,  226 

Wash    water    as    source    of 

bacteria 233-40 

Washing 219 

MILK,  GERM  CONTENT  OF— 

I.  AS   INFLUENCED   BY 

THE  FACTORS  AT  THE 

BARN 21-52 

II.  AS      INFLUENCED      BY 

UTENSILS    215-57 

Mimosa 135 

pudica 133 

Morning  glory,  Attempted  in- 
fection with  sweet-clover  bac- 
teria    157 

Hucuna 135,  139 

utilis 123,  131,  134,  135,  136 

Mustard,  Attempts  to  grow  leg- 


PAGE 

ume  bacteria  on 115 

Myrica 145,  149-50,  160 

gale 145 

Neoga,      111.,      Spraying     experi- 
ments    432-48 

New   York    (Geneva)    Agr.   Exp. 
Sta.,   Investigations  of  germ 

content  of  milk 25-26,  217 

Nitrogen  « 

Content  of  different  crops.  . .   532 

Loss  from  erosion 522-25 

Needed  by   soils  subject   to 

erosion 531 

Requirements  for  corn 532-33 

Nitrogen  fixation 115 

Non-legumes  concerned  in ...  145-50 
By  legumes,  bibliography. ..  161-78 
Nodule  bacteria,  varieties  of. ... 

125-40,  160 

Nodules,  Non-legume  root,  Bibli- 
ography   179-81 

of    the    Leguminoeae,    Histol- 
ogy   141-44 

Non-legume  root  nodules,  Bibliog- 
raphy  179-81 

Nozzles  for  spraying.  ..  .445-56,  448, 

456-57,  499-501 

Oat  straw,  Nitrogen  content  of..   532 

Winter 106-08 

Onobrychis  sativa 149 

Orchards,    see    Spraying    experi- 
ments 

Orchestes  canus  452 

Ornithopus 135 

sativus 137,  149 

Partridge  pea,  see  Cassia 
Pea,  see  Pisum 
Peanut,  see  Arachis 

Phcbseolus 119,  127,  135,  139 

angustifolia 137 

multiflorus 133,  137 

milgaris 123,  133,   134, 

137,  148-49,  151,  154 
Phosphorus,  Loss  from  erosion. 522-25 

Phyllosticta  solitaria   452 

PIGS,     DIGESTION     EXPERI- 
MENTS WITH 53-94 

Chemical  composition  of  feces 

56-57,  60-61,  73,  76-77 

of  feeds 56-57,  73 

Coefficients  of  digestibility 

61-65,   75-80 

Average 66,  88 

of  ground  barley 81 

of  ground  barley  and  ground 

corn 83 

of  ground  corn 68,  82 

of  middlings 67 

of  middlings  and  ground  corn     69 
showing  individuality  of  pigs 
71,  86 


INDEX 


561 


PAGE 

Conclusion 89-90 

Digestion  harness    (illus) 94 

Digestion  stalls 55-56,  91-93 

Individuality  as  to  thoroncss  of 

digestion 70-72,  85-87 

Influence  of  one  feed  upon  di- 
gestibility  of   another 

65-70,  80-85,  89 

Objects 55 

Plan  of  experiments — 

1913-14 55-56 

1914-15 72-73 

Rations    56,72-73,  88 

Weight  of  feces..  .57,  58-59,  74-75 

of  feeds 58-59,  74-75 

of  pigs  58-59,  74-75 

of  urine 58-59,  74-75 

of  water 58-59,  74-75 

Piitum 119,  127,  135,  139 

arvense 123,  133,  135,  148 

sativum 133,  134,  135,  136,  152 

xatii'iim  arvcnsc 136 

Podocarpus 145,  160 

Potomac     river     basin,     Run-off 

from 518 

Pscudomonas  radicicola 

The  organism 116-23 

Experiments  attempting  infec- 
tion of  non-legumes.  .155-59,  160 

Rainfall  in  Illinois 517 

and  run-off 518-19 

Robinia  pseudo-acacia.  .131,  133,  134, 

135,  137,  153 

Run-off,  see  Rainfall 

Russet,  Bordeaux. .  .429,  432,  437-38, 

440,  445,  449-51,  454-57,  460-65, 

470-71,    474,    475,    477-84,    486, 

489,  494,  499-502 

Lime  sulfur 435,  460,  467- 

70,  474,  480 
Rye 

as  cover  crop 520 

to  improve  eroded  land 531 

Winter 99,  101,  106-08 

San  Jose  scale,  Spray  for 505 

Savannah     river    basin,     Run-off 

from 518 

Scab,  see  Apple  scab 
Sensitive  plant,  see  Mimosa 
Serradella,  see  Ornithopus 
Sheet  washing,  see  Erosion 
Soil 

Changes  produced  by  erosion.  .   525 
Organic-matter  content  of  Illi- 
nois     529 

subject  to  erosion 522-23 

Soil  survey  of   Illinois,   Area   of 

broken  and  hilly  land.  .  .  .514-15 

Sooty  blotch.... 460-71,  472,  474-89, 

491,  493,  497,  498 


PAGE 

Sprays  for 506-07 

SOYBEANS     AND     COWPEAS 

IN  ILLINOIS , 1-20 

Soybean 

Culture 4 

Harvesting  of   5,  6 

Inoculation 5 

Tests  with 6-20 

See  also  Glycine 

Sphaeropsisf  malorum .452,  460 

Spoon  river  basin,  Run-off  from.   518 
Spraying    experiments    in    apple 

orchards 427-509 

Amount  of  spray,  Varying. 455,  457 
Applications 

Fourth  summer 

436-37,   4S1,   483,  484 

General  effectiveness 

490,  493-94 

Times  of 431,  505-08 

Nozzles 

Effectiveness  of  standard... 

445-46,  448 

Varying  size  of.  .456-57,  499-501 
Objects  of  1913-14  experiments  429 
Orchards 

Flora,  1913   451 

Griggsville,  1913 458 

1914 472 

Neoga,    1913    432 

1914 441 

Pressure,  Varying  ....437-39,  445, 
454-55,  457,  499-501 

Recommendations 505-08 

Records 431 

Sprays  for  apple  trees 

Acetate    of   lead    with    copper 

ferrocyanide 487,  488,  489 

Arsenate  of  lead 

Brands  of  

. . .434-36,  442-45,  484-86,  495 

Effectiveness 490-94 

Formula 431 

Paste  and  powered  compared 

464,  465,  471 

used  alone    

.  .  .434-35,  442-44,  447-48,  471 
with  Bordeaux  and  lime  sul- 
fur   461,  476 

with  lime  sulfur 

.  .434-36,  442-45,  448,  464,  471 
Bordeaux 

Effectiveness 490-94 

Formula 430 

with  lime  sulfur,  see  Sprays 
for  apple  trees,  Lime  sul- 
fur 

Sec  also  Russet 
Calcium  hyposulfite.  .  .445,  448,  495 


562 


VOLUME  14 


PAGE 

Copper  ferrocyanide 

445,   448,   471,  495 

prepared  in  different  ways.  . 

' 466,  467-68,  498-99 

'  with  acetate  of  lead. 487,  488,  489 

with  arsenate  of  lead 437 

Lime  sulfur 

compared  with  atomic  sulfur 

and  soluble  sulfur 

468,   469,  486,  487 

Effectiveness    490-94 

Formula  for  commercial ....   430 

for  home-made 430-31 

Various  strengths  

467,   481,  482,  504 

Lime  sulfur  and  Bordeaux 

Interchanged 

461,  463,  475-77,  501-02 

Light  and  heavy  applications 

469,  470,  478,  479-81 

Relative  values   of 

459-60,  473-75,  494-95 

Special,  for  codling  moth . .  .  502-04 

Drenching 477-79,  502  . 

for  delayed  broods. .  .446-47,  503 
Fourth     summer     spray    for 

second   brood   436-37 

Sulfur,  Atomic 445,  448,  468, 

469,  471,  486,  487,  498 

Soluble 445,  448,  468, 

469,  471,  486,  487,  498 

Tuber  tonic 445,  448,  498 

Strawberry  plants,  Attempted  in- 
fection     with      sweet-clover 

bacteria 157,  159 

Strophostyles 119,  135,  139 

helvola 133,  134,  135,  137,  154 

Sweet  pea,  see  Lathyrus 
Swine,  see  Pigs 

Symbiosis   between    legume    bac- 
teria and  non-legumes. ..  .111-81 

Experiments 152-59 

Tankage 63,  80 

Tent  caterpillar,  Spray  for 505 

Terraces  for  cultivated  slopes. 535-36 


PAGE 
Tick  trefoil,  see  Dcsmodinm 

Tiling  to  reduce  erosion 535 

Tillage     for     land     subject     to 

erosion 533-35 

Tomato,  Attempted  infection  with 

sweet-clover    bacteria 155-57 

Trifolium 119,  127,  135,  139 

alcxandrianum 136 

hybridum 136 

incarnatum 136 

medium 136 

pratense 123,  134,  148, 

152,  153,  154 

pratense  perenne 136 

repens 136 

Trigonella 119,  135,  139 

foemim-graecum 

.  133,  134,  135,  136,  149 

Urbana,  111.,  Variety  tests  of  win- 
ter wheat    101-04 

Urbana  experiment  field 97 

Velvet  bean,  see  Mucuna 
Vetch,  see  Vicia 

Vicia 119,  127,  135,  139 

angustifolia 136 

daysiecarpa 136 

faba 123,  133,  136,  154 

sativa •. 136 

villosa 122,  123,  134,  136,  148 

Vienna,  111.,  Reclamation  experi- 
ment at   543-50 

Vigna 119,  127,  135,  139,  140 

sinensis 123,  127,  129,  131, 

134,  135,  136,  149,  153,  154 
WASHING     OF     SOILS     AND 
METHODS    OF    PREVEN- 
TION  511-50 

Wheat,  Winter 

Characteristics    of    vari- 
eties   109-10 

Tests  of    97-110 

Wheat    straw,    Nitrogen    content 

of 532 

Winter  grains,  see  Grains 

Yellow  leaf... 438,  474,  475,  479,  486 


UNIVERSITY  OF  ILLINOIS-URBANA 


